diff --git a/src/bliss/bliss.cc b/src/bliss/bliss.cc
index 037e0bc..61e8d79 100644
--- a/src/bliss/bliss.cc
+++ b/src/bliss/bliss.cc
@@ -10,9 +10,9 @@
 /*
   Copyright (c) 2003-2015 Tommi Junttila
   Released under the GNU Lesser General Public License version 3.
-  
+
   This file is part of bliss.
-  
+
   bliss is free software: you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as published by
   the Free Software Foundation, version 3 of the License.
@@ -55,7 +55,7 @@ static void usage(FILE* const fp, const char* argv0)
         program_name++;
     else
         program_name = argv0;
-    if (!program_name or *program_name == 0)
+    if (!program_name || *program_name == 0)
         program_name = "bliss";
 
     fprintf(fp,
@@ -96,7 +96,7 @@ static void parse_options(const int argc, const char** argv)
     for (int i = 1; i < argc; i++) {
         if (strcmp(argv[i], "-can") == 0)
             opt_canonize = true;
-        else if ((strncmp(argv[i], "-ocan=", 6) == 0) and
+        else if ((strncmp(argv[i], "-ocan=", 6) == 0) &&
                  (strlen(argv[i]) > 6)) {
             opt_canonize = true;
             opt_output_can_file = argv[i] + 6;
@@ -112,7 +112,7 @@ static void parse_options(const int argc, const char** argv)
             opt_use_component_recursion = false;
         else if (strcmp(argv[i], "-cr=y") == 0)
             opt_use_component_recursion = true;
-        else if ((strncmp(argv[i], "-sh=", 4) == 0) and (strlen(argv[i]) > 4)) {
+        else if ((strncmp(argv[i], "-sh=", 4) == 0) && (strlen(argv[i]) > 4)) {
             opt_splitting_heuristics = argv[i] + 4;
         } else if (strcmp(argv[i], "-version") == 0) {
             fprintf(stdout, "bliss version %s\n", bliss::version);
@@ -268,7 +268,7 @@ int main(const int argc, const char** argv)
     }
 
     /* Output search statistics */
-    if (verbose_level > 0 and verbstr)
+    if (verbose_level > 0 && verbstr)
         stats.print(verbstr);
 
     if (verbose_level > 0) {
diff --git a/src/bliss/graph.cc b/src/bliss/graph.cc
index 60458eb..ef2c6a1 100644
--- a/src/bliss/graph.cc
+++ b/src/bliss/graph.cc
@@ -785,7 +785,7 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
         if (opt_use_comprec) {
             CR_CEP& cep = cr_cep_stack[current_node.cr_cep_index];
             if (cep.first_checked == true &&
-                current_node.fp_extendable == TreeNode::MAYBE and
+                current_node.fp_extendable == TreeNode::MAYBE &&
                 !search_stack[cep.creation_level].fp_on) {
                 current_node.fp_extendable = TreeNode::NO;
             }
@@ -812,7 +812,7 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
                 continue;
             }
             if (current_node.fp_extendable == TreeNode::NO &&
-                (!canonical or current_node.cmp_to_best_path < 0)) {
+                (!canonical || current_node.cmp_to_best_path < 0)) {
                 if (opt_use_failure_recording) {
                     TreeNode& parent_node = search_stack[current_level - 1];
                     if (parent_node.fp_on)
@@ -913,7 +913,7 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
              * a minimal orbit representative w.r.t. first_path_orbits */
                 for (unsigned int i = cell->length; i > 0; i--, ep++) {
                     if ((int)(*ep) > current_node.split_element &&
-                        *ep < next_split_element and
+                        *ep < next_split_element &&
                         first_path_orbits.is_minimal_representative(*ep)) {
                         next_split_element = *ep;
                         //next_split_element_pos = ep;
@@ -924,9 +924,9 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
              * a minimal orbit representative w.r.t. best_path_orbits */
                 for (unsigned int i = cell->length; i > 0; i--, ep++) {
                     if ((int)(*ep) > current_node.split_element &&
-                        *ep < next_split_element and
-                        best_path_orbits.is_minimal_representative(*ep) and
-                        (!opt_use_long_prune or
+                        *ep < next_split_element &&
+                        best_path_orbits.is_minimal_representative(*ep) &&
+                        (!opt_use_long_prune ||
                          current_node.long_prune_redundant.find(*ep) ==
                              current_node.long_prune_redundant.end())) {
                         next_split_element = *ep;
@@ -937,8 +937,8 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
                 /* Find the next larger splitting element */
                 for (unsigned int i = cell->length; i > 0; i--, ep++) {
                     if ((int)(*ep) > current_node.split_element &&
-                        *ep < next_split_element and
-                        (!opt_use_long_prune or
+                        *ep < next_split_element &&
+                        (!opt_use_long_prune ||
                          current_node.long_prune_redundant.find(*ep) ==
                              current_node.long_prune_redundant.end())) {
                         next_split_element = *ep;
@@ -1090,7 +1090,7 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
            * if canonical labeling is desired, also worse than the
            * current best path */
             if (refine_equal_to_first == false &&
-                (!canonical or (refine_cmp_to_best < 0))) {
+                (!canonical || (refine_cmp_to_best < 0))) {
                 /* Yes, backtrack */
                 stats.nof_bad_nodes++;
                 if (current_node.fp_cert_equal == true &&
@@ -1125,8 +1125,8 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
         child_node.in_best_path = false;
 
         child_node.fp_cert_equal = refine_equal_to_first;
-        if (current_node.fp_extendable == TreeNode::NO or
-            (current_node.fp_extendable == TreeNode::MAYBE and
+        if (current_node.fp_extendable == TreeNode::NO ||
+            (current_node.fp_extendable == TreeNode::MAYBE &&
              child_node.fp_cert_equal == false))
             child_node.fp_extendable = TreeNode::NO;
         else
@@ -1247,7 +1247,7 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
                     CR_CEP& cep = cr_cep_stack[cr_cep_index];
 
                     /* First, compare with respect to the first path */
-                    if (first_path_info.empty() or child_node.fp_cert_equal) {
+                    if (first_path_info.empty() || child_node.fp_cert_equal) {
                         if (cep.first_checked == false) {
                             /* First time, go to the next component */
                             cep.first_checked = true;
@@ -1392,7 +1392,7 @@ void AbstractGraph::search(const bool canonical, Stats& stats)
                 // cr_cep_stack[cr_cep_index].discrete_cell_limit)
                 if (nucr_find_first_component(cr_level, cr_component,
                                               cr_component_elements,
-                                              next_split_cell) == true and
+                                              next_split_cell) == true &&
                     p.nof_discrete_cells() + cr_component_elements <
                         cr_cep_stack[cr_cep_index].discrete_cell_limit) {
                     const unsigned int next_cr_level =
@@ -2309,7 +2309,7 @@ bool Digraph::split_neighbourhood_of_cell(Partition::Cell* const cell)
                 cert_add_redundant(CERT_SPLIT, c->first, c->length);
                 /* No need to continue? */
                 if (refine_compare_certificate &&
-                    (refine_equal_to_first == false) and
+                    (refine_equal_to_first == false) &&
                     (refine_cmp_to_best < 0))
                     goto worse_exit;
             }
@@ -2371,7 +2371,7 @@ bool Digraph::split_neighbourhood_of_cell(Partition::Cell* const cell)
                 cert_add_redundant(CERT_SPLIT, c->first, c->length);
                 /* No need to continue? */
                 if (refine_compare_certificate &&
-                    (refine_equal_to_first == false) and
+                    (refine_equal_to_first == false) &&
                     (refine_cmp_to_best < 0))
                     goto worse_exit;
             }
@@ -2545,7 +2545,7 @@ bool Digraph::split_neighbourhood_of_unit_cell(Partition::Cell* const unit_cell)
                 cert_add(CERT_EDGE, unit_cell->first, i);
                 /* No need to continue? */
                 if (refine_compare_certificate &&
-                    (refine_equal_to_first == false) and
+                    (refine_equal_to_first == false) &&
                     (refine_cmp_to_best < 0))
                     goto worse_exit;
             }
@@ -2662,7 +2662,7 @@ bool Digraph::split_neighbourhood_of_unit_cell(Partition::Cell* const unit_cell)
                 cert_add(CERT_EDGE, i, unit_cell->first);
                 /* No need to continue? */
                 if (refine_compare_certificate &&
-                    (refine_equal_to_first == false) and
+                    (refine_equal_to_first == false) &&
                     (refine_cmp_to_best < 0))
                     goto worse_exit;
             }
@@ -3025,7 +3025,7 @@ Partition::Cell* Digraph::sh_first_smallest_max_neighbours()
             neighbour_cell->max_ival = 0;
         }
 
-        if ((value > best_value) or
+        if ((value > best_value) ||
             (value == best_value && cell->length < best_size)) {
             best_value = value;
             best_size = cell->length;
@@ -3418,13 +3418,13 @@ bool Digraph::nucr_find_first_component(const unsigned int level,
         /*| Phase 3: splitting heuristics */
         switch (sh) {
             case shs_f:
-                if (sh_return == 0 or cell->first <= sh_first) {
+                if (sh_return == 0 || cell->first <= sh_first) {
                     sh_return = cell;
                     sh_first = cell->first;
                 }
                 break;
             case shs_fs:
-                if (sh_return == 0 or cell->length < sh_size or
+                if (sh_return == 0 || cell->length < sh_size ||
                     (cell->length == sh_size && cell->first <= sh_first)) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -3432,7 +3432,7 @@ bool Digraph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_fl:
-                if (sh_return == 0 or cell->length > sh_size or
+                if (sh_return == 0 || cell->length > sh_size ||
                     (cell->length == sh_size && cell->first <= sh_first)) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -3440,7 +3440,7 @@ bool Digraph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_fm:
-                if (sh_return == 0 or nuconn > sh_nuconn or
+                if (sh_return == 0 || nuconn > sh_nuconn ||
                     (nuconn == sh_nuconn && cell->first <= sh_first)) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -3448,9 +3448,9 @@ bool Digraph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_fsm:
-                if (sh_return == 0 or nuconn > sh_nuconn or
-                    (nuconn == sh_nuconn and
-                     (cell->length < sh_size or
+                if (sh_return == 0 || nuconn > sh_nuconn ||
+                    (nuconn == sh_nuconn &&
+                     (cell->length < sh_size ||
                       (cell->length == sh_size && cell->first <= sh_first)))) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -3459,9 +3459,9 @@ bool Digraph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_flm:
-                if (sh_return == 0 or nuconn > sh_nuconn or
-                    (nuconn == sh_nuconn and
-                     (cell->length > sh_size or
+                if (sh_return == 0 || nuconn > sh_nuconn ||
+                    (nuconn == sh_nuconn &&
+                     (cell->length > sh_size ||
                       (cell->length == sh_size && cell->first <= sh_first)))) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -4098,7 +4098,7 @@ bool Graph::split_neighbourhood_of_cell(Partition::Cell* const cell)
                 cert_add_redundant(CERT_SPLIT, c->first, c->length);
                 /* No need to continue? */
                 if (refine_compare_certificate &&
-                    (refine_equal_to_first == false) and
+                    (refine_equal_to_first == false) &&
                     (refine_cmp_to_best < 0))
                     goto worse_exit;
             }
@@ -4266,7 +4266,7 @@ bool Graph::split_neighbourhood_of_unit_cell(Partition::Cell* const unit_cell)
                 cert_add(CERT_EDGE, unit_cell->first, i);
                 /* No need to continue? */
                 if (refine_compare_certificate &&
-                    (refine_equal_to_first == false) and
+                    (refine_equal_to_first == false) &&
                     (refine_cmp_to_best < 0))
                     goto worse_exit;
             }
@@ -4542,7 +4542,7 @@ Partition::Cell* Graph::sh_first_smallest_max_neighbours()
                 value++;
             neighbour_cell->max_ival = 0;
         }
-        if ((value > best_value) or
+        if ((value > best_value) ||
             (value == best_value && cell->length < best_size)) {
             best_value = value;
             best_size = cell->length;
@@ -4588,7 +4588,7 @@ Partition::Cell* Graph::sh_first_largest_max_neighbours()
                 value++;
             neighbour_cell->max_ival = 0;
         }
-        if ((value > best_value) or
+        if ((value > best_value) ||
             (value == best_value && cell->length > best_size)) {
             best_value = value;
             best_size = cell->length;
@@ -4826,13 +4826,13 @@ bool Graph::nucr_find_first_component(const unsigned int level,
 
         switch (sh) {
             case shs_f:
-                if (sh_return == 0 or cell->first <= sh_first) {
+                if (sh_return == 0 || cell->first <= sh_first) {
                     sh_return = cell;
                     sh_first = cell->first;
                 }
                 break;
             case shs_fs:
-                if (sh_return == 0 or cell->length < sh_size or
+                if (sh_return == 0 || cell->length < sh_size ||
                     (cell->length == sh_size && cell->first <= sh_first)) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -4840,7 +4840,7 @@ bool Graph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_fl:
-                if (sh_return == 0 or cell->length > sh_size or
+                if (sh_return == 0 || cell->length > sh_size ||
                     (cell->length == sh_size && cell->first <= sh_first)) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -4848,7 +4848,7 @@ bool Graph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_fm:
-                if (sh_return == 0 or nuconn > sh_nuconn or
+                if (sh_return == 0 || nuconn > sh_nuconn ||
                     (nuconn == sh_nuconn && cell->first <= sh_first)) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -4856,9 +4856,9 @@ bool Graph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_fsm:
-                if (sh_return == 0 or nuconn > sh_nuconn or
-                    (nuconn == sh_nuconn and
-                     (cell->length < sh_size or
+                if (sh_return == 0 || nuconn > sh_nuconn ||
+                    (nuconn == sh_nuconn &&
+                     (cell->length < sh_size ||
                       (cell->length == sh_size && cell->first <= sh_first)))) {
                     sh_return = cell;
                     sh_first = cell->first;
@@ -4867,9 +4867,9 @@ bool Graph::nucr_find_first_component(const unsigned int level,
                 }
                 break;
             case shs_flm:
-                if (sh_return == 0 or nuconn > sh_nuconn or
-                    (nuconn == sh_nuconn and
-                     (cell->length > sh_size or
+                if (sh_return == 0 || nuconn > sh_nuconn ||
+                    (nuconn == sh_nuconn &&
+                     (cell->length > sh_size ||
                       (cell->length == sh_size && cell->first <= sh_first)))) {
                     sh_return = cell;
                     sh_first = cell->first;