Compilare: user.cpp: In function ‘void bfs()’: user.cpp:36:43: warning: suggest parentheses around comparison in operand of ‘|’ [-Wparentheses] if (ok(xx,yy) && (dst[xx][yy] == 0 | dst[xx][yy] > dst[x][y] + 1)) ^ user.cpp: In function ‘int main()’: user.cpp:76:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("barbar.in","r",stdin); ^ user.cpp:77:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("barbar.out","w",stdout); ^ user.cpp:79:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:82:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",ar[i] + 1); ^