Compilare: user.cpp: In function ‘bool check(int)’: user.cpp:39:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (pas = 0; pas < best.size(); pas++) { ^ user.cpp:33:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, pas, wh, need, wh2; ^ user.cpp: In function ‘bool recon(int)’: user.cpp:74:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (pas = 0; pas < best.size(); pas++) { ^ user.cpp:68:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, pas, wh, need, wh2; ^ user.cpp: In function ‘int main()’: user.cpp:149:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < sol[i].size(); j++) ^ user.cpp:108:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("danger.in", "r", stdin); ^ user.cpp:109:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("danger.out", "w", stdout); ^ user.cpp:111:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:123:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &mat[i][j - 1]); ^