Compilare: user.cpp: In function ‘bool cupleaza(int)’: user.cpp:49:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < gr[index].size(); ++i) { ^ user.cpp:58:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < gr[index].size(); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:71:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("canibali.in", "r", stdin); ^ user.cpp:72:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("canibali.out", "w", stdout); ^ user.cpp:76:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:78:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &v[i].x, &v[i].y, &v[i].z, &v[i].t); ^