Compilare: user.cpp: In function ‘int main()’: user.cpp:70:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k = 0; k < v[j + 1].size(); k++) ^ user.cpp:23:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("albine.in", "r", stdin); ^ user.cpp:24:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("albine.out", "w", stdout); ^ user.cpp:25:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:29:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j]); ^