When I use this code in Visual Studio, it works normally, but when I paste it to Codewars, this error appears. What did I suppose to do? Also, is the output function are valid?
This code for Skyscrapers 4x4 kata from codewars https://www.codewars.com/kata/5671d975d81d6c1c87000022/train/cpp Also can change it to 6x6 (and any other size) easily.
STDERR
UndefinedBehaviorSanitizer:DEADLYSIGNAL
==1==ERROR: UndefinedBehaviorSanitizer: SEGV on unknown address 0x0000ffffffff (pc 0x0000004254dd bp 0x000000000000 sp 0x7fff88975810 T1)
==1==The signal is caused by a WRITE memory access.
==1==WARNING: invalid path to external symbolizer!
==1==WARNING: Failed to use and restart external symbolizer!
#0 0x4254dc (/workspace/test 0x4254dc)
#1 0x42cf0a (/workspace/test 0x42cf0a)
#2 0x42b79e (/workspace/test 0x42b79e)
#3 0x42b31f (/workspace/test 0x42b31f)
#4 0x42af7b (/workspace/test 0x42af7b)
#5 0x42f2f5 (/workspace/test 0x42f2f5)
#6 0x42566d (/workspace/test 0x42566d)
#7 0x7f929bdf5bf6 (/lib/x86_64-linux-gnu/libc.so.6 0x21bf6)
#8 0x404249 (/workspace/test 0x404249)
UndefinedBehaviorSanitizer can not provide additional info.
==1==ABORTING
Code:
#include <iostream>
#include <vector>
#include <map>
#include <algorithm>
#include <iterator>
#include <string>
using namespace std;
void print(vector<int> array) {
for (unsigned int i = 0; i < array.size(); i ) cout << array[i] << " ";
}
int check_visible(vector<int> row) {
int visible = 0, current_height = 0;
for (unsigned int i = 0; i < row.size(); i ) {
if (row[i] > current_height) {
current_height = row[i];
visible ;
}
}
return visible;
}
class possible_vars {
public:
vector<int> vars;
/*possible_vars& operator= (const possible_vars& vars2)
{
vars = vars2.vars;
return *this;
}*/
possible_vars& operator= (const vector<int>& vars2)
{
vars = vars2;
return *this;
}
possible_vars(int bsize) {
for (int i = 0; i < bsize; i ) vars.push_back(i 1);
}
possible_vars(vector<int> input) {
vars = input;
}
int size() {
return vars.size();
}
bool remove_variant(int num) {
bool is_changed = false;
for (unsigned int i = 0; i < vars.size(); i ) {
if (vars[i] == num) {
vars.erase(vars.begin() i);
is_changed = true;
break;
}
}
return is_changed;
}
bool is_var_here(int var) {
if (find(vars.begin(), vars.end(), var) != vars.end()) return true;
else return false;
}
};
class skyscrapers {
public:
vector<vector<possible_vars>> solution;
vector<vector<short>> solution_static;
vector<int> clues;
vector<vector<int>> patterns;
vector<int> pattern;
int basic_size;
skyscrapers(int size_of_field) {
solution = vector<vector<possible_vars>>(size_of_field, vector<possible_vars>(size_of_field,possible_vars(size_of_field)));
solution_static = vector<vector<short>>(size_of_field, vector<short>(size_of_field, false));
clues = vector<int>(size_of_field * size_of_field);
basic_size = size_of_field;
}
vector<vector<possible_vars>> patterns_by_det;
vector<vector<possible_vars>> excluding_patterns;
void generate_excluding_base() {
possible_vars for_one_number(basic_size);
vector<possible_vars> for_one_pattern;
for (int i = 0; i < basic_size; i ) {
for_one_pattern.push_back(for_one_number);
}
for (int i = 0; i < basic_size; i ) {
excluding_patterns.push_back(for_one_pattern);
}
}
void generate_patterns() {
vector<int> base;
for (int i = 0; i < basic_size; i ) {
base.push_back(i 1);
}
generate_patterns_re(base);
int seen;
patterns_by_det = vector<vector<possible_vars>>(basic_size);
for (unsigned int i = 0; i < patterns.size(); i ) {
seen = check_visible(patterns[i]);
patterns_by_det[seen - 1].push_back(possible_vars(patterns[i]));
}
generate_excluding_base();
for (unsigned int i = 0; i < patterns_by_det.size(); i ) {
for (unsigned int j = 0; j < patterns_by_det.size(); j ) {
for (unsigned int k = 0; k < patterns_by_det[i].size(); k ) {
excluding_patterns[i][j].remove_variant(patterns_by_det[i][k].vars[j]);
}
}
}
}
void generate_patterns_re(vector<int> possible_vars) {
vector<int> next;
if (possible_vars.size() > 1) {
for (unsigned int i = 0; i < possible_vars.size(); i ) {
pattern.push_back(possible_vars[i]);
next = possible_vars;
next.erase(next.begin() i);
generate_patterns_re(next);
pattern.pop_back();
}
}
else {
pattern.push_back(possible_vars[0]);
patterns.push_back(pattern);
pattern.pop_back();
}
}
vector<possible_vars*> get_row(int row_index) {
vector<possible_vars*> row;
possible_vars* cell;
if (row_index / basic_size == 0) {
for (int i = 0; i < basic_size; i ) {
cell = &solution[i][row_index % basic_size];
row.push_back(cell);
}
}
else if (row_index / basic_size == 1) {
for (int i = 0; i < basic_size; i ) {
cell = &solution[row_index % basic_size][basic_size - 1 - i];
row.push_back(cell);
}
}
else if (row_index / basic_size == 2) {
for (int i = 0; i < basic_size; i ) {
cell = &solution[basic_size - 1 - i][basic_size - 1 - row_index % basic_size];
row.push_back(cell);
}
}
else if (row_index / basic_size == 3) {
for (int i = 0; i < basic_size; i ) {
cell = &solution[basic_size - 1 - row_index % basic_size][i];
row.push_back(cell);
}
}
return row;
}
vector<short*> get_static_row(int row_index) {
vector<short*> row;
short* cell;
if (row_index / basic_size == 0) {
for (int i = 0; i < basic_size; i ) {
cell = &solution_static[i][row_index % basic_size];
row.push_back(cell);
}
}
else if (row_index / basic_size == 1) {
for (int i = 0; i < basic_size; i ) {
cell = &solution_static[row_index % basic_size][basic_size - 1 - i];
row.push_back(cell);
}
}
else if (row_index / basic_size == 2) {
for (int i = 0; i < basic_size; i ) {
cell = &solution_static[basic_size - 1 - i][basic_size - 1 - row_index % basic_size];
row.push_back(cell);
}
}
else if (row_index / basic_size == 3) {
for (int i = 0; i < basic_size; i ) {
cell = &solution_static[basic_size - 1 - row_index % basic_size][i];
row.push_back(cell);
}
}
return row;
}
void remove_all_vars(int y, int x) {
for (int i = 0; i < basic_size; i ) {
if (i != x) solution[y][i].remove_variant(solution[y][x].vars[0]);
}
for (int i = 0; i < basic_size; i ) {
if (i != y) solution[i][x].remove_variant(solution[y][x].vars[0]);
}
}
bool normalize() {
bool is_changed = false;
for (int i = 0; i < basic_size; i ) {
for (int j = 0; j < basic_size; j ) {
if (solution_static[i][j] == false and solution[i][j].vars.size() == 1) {
solution_static[i][j] = true;
remove_all_vars(i, j);
is_changed = true;
}
}
}
return is_changed;
}
bool add_obvious() {
bool is_changed = false;
map<int, int> counting;
for (int i = 0; i < basic_size; i ) counting.insert(pair<int, int>(i 1, 0));
for (int i = 0; i < basic_size; i ) {
for (int j = 1; j <= basic_size; j ) counting[j] = 0;
for (int j = 0; j < basic_size; j ) {
for (int k = 0; k < solution[i][j].size(); k ) {
counting[solution[i][j].vars[k]] = 1;
}
}
for (int k = 1; k <= basic_size; k ) {
if (counting[k] == 1) {
for (int j = 0; j < basic_size; j ) {
if (solution_static[i][j] == false and solution[i][j].is_var_here(k)) {
solution[i][j].vars = { k };
solution_static[i][j] = true;
remove_all_vars(i, j);
is_changed = true;
}
}
}
}
}
for (int j = 0; j < basic_size; j ) {
for (int j = 1; j <= basic_size; j ) counting[j] = 0;
for (int i = 0; i < basic_size; i ) {
for (int k = 0; k < solution[i][j].size(); k ) {
counting[solution[i][j].vars[k]] = 1;
}
}
for (int k = 1; k <= basic_size; k ) {
if (counting[k] == 1) {
for (int i = 0; i < basic_size; i ) {
if (solution_static[i][j] == false and solution[i][j].is_var_here(k)) {
solution[i][j].vars = { k };
solution_static[i][j] = true;
remove_all_vars(i, j);
is_changed = true;
}
}
}
}
}
return is_changed;
}
bool fix_matrix() {
bool is_changed = false, is_changed_global = false;
do {
is_changed = normalize();
is_changed_global = is_changed;
} while (is_changed == true);
do {
is_changed = add_obvious();
is_changed_global = is_changed;
} while (is_changed == true);
return is_changed_global;
}
bool use_excluding_patterns() {
bool is_changed = false;
vector<possible_vars*> row;
int current_value;
for (unsigned int curr_clue = 0; curr_clue < clues.size(); curr_clue ) {
if (clues[curr_clue] != 0) {
row = get_row(curr_clue);
current_value = clues[curr_clue] - 1;
for (unsigned int i = 0; i < excluding_patterns[current_value].size(); i ) {
for (int j = 0; j < excluding_patterns[current_value][i].size(); j ) {
is_changed = row[i]->remove_variant(excluding_patterns[current_value][i].vars[j]);
}
}
}
}
return is_changed;
}
bool use_patterns() {
bool is_changed = false, is_suitable;
vector<possible_vars*> row;
vector<short*> static_row;
int current_value;
vector<possible_vars> current_patterns;
for (unsigned int curr_clue = 0; curr_clue < clues.size(); curr_clue ) {
if (clues[curr_clue] != 0) {
row = get_row(curr_clue);
static_row = get_static_row(curr_clue);
current_value = clues[curr_clue] - 1;
current_patterns = patterns_by_det[current_value];
for (unsigned int i = 0; i < current_patterns.size(); i ) {
//for (int print = 0; print < current_patterns[i].size(); print ) cout << current_patterns[i].vars[print] << " ";
//cout << endl;
for (int j = 0; j < current_patterns[i].size(); j ) {
is_suitable = row[j]->is_var_here(current_patterns[i].vars[j]);
// cout << j 1 << "-> " << is_suitable << endl;
if (is_suitable == false) {
current_patterns.erase(current_patterns.begin() i);
i--;
//cout << endl << "Erased, now current patterns:" << endl;
/*for (int print1 = 0; print1 < current_patterns.size(); print1 ) {
for (int print2 = 0; print2 < current_patterns[print1].size(); print2 ) cout << current_patterns[print1].vars[print2] << " ";
cout << endl;
}
cout << endl;*/
break;
}
}
}
if (current_patterns.size() == 1) {
for (unsigned int i = 0; i < row.size(); i ) {
if (*static_row[i] == false) {
*static_row[i] = true;
is_changed = true;
*row[i] = possible_vars(vector<int>(1, current_patterns[0].vars[i]));
}
}
}
}
}
return is_changed;
}
void print() {
for (int i = 0; i < 4; i ) {
for (int j = 0; j < 4; j ) {
for (int k = 0; k < solution[i][j].size(); k ) cout << solution[i][j].vars[k];
cout << " ";
}
cout << endl;
}
cout << endl;
}
};
int** SolvePuzzle(int* clues) {
skyscrapers result(4);
result.generate_patterns();
for (int i = 0; i < 16; i ) {
result.clues[i] = clues[i];
}
bool is_changed = true;
result.use_excluding_patterns();
result.fix_matrix();
while (is_changed) {
is_changed = result.use_patterns();
is_changed = result.fix_matrix();
}
int** answer[4][4];
for (unsigned int i = 0; i < result.solution.size(); i ) {
for (unsigned int j = 0; j < result.solution[i].size(); j ) {
*answer[i][j] = &result.solution[i][j].vars[0];
}
}
return **answer;
}
CodePudding user response：
This block of code appears suspicious for several reasons:
int** answer[4][4];
for (unsigned int i = 0; i < result.solution.size(); i ) {
for (unsigned int j = 0; j < result.solution[i].size(); j ) {
*answer[i][j] = &result.solution[i][j].vars[0];
}
}
return **answer;
&result.solution[i][j].vars[0] is a pointer to something inside that result object. As soon as the function returns, result will destruct and the pointers assigned to answer[i][j] is no longer valid when the function returns.
Also, returning **answer is really suspicious. With regards to a local 2-d array, this statement would in essence only return the int** inside answer[0][0]. None of the other values inside answer would be passed back - even if result wasn't destructing.
CodePudding user response：
The problem is that you made a 4x4 array of int**. Here is the fixed code:
int** answer = new int*[4];
for (unsigned int i = 0; i < result.solution.size(); i ) {
answer[i] = new int[4];
for (unsigned int j = 0; j < result.solution[i].size(); j ) {
answer[i][j] = result.solution[i][j].vars[0];
}
}