Compilare: user.cpp: In function ‘int main()’: user.cpp:153:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < id.size(); ) { ^ user.cpp:160:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (j < id.size()) { ^ user.cpp:127:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("demolish.in","r",stdin); ^ user.cpp:128:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("demolish.out","w",stdout); ^ user.cpp:130:46: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d", &n, &m, &k, &dx, &dy); ^ user.cpp:134:71: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d", &xx1[i], &yy1[i], &xx2[i], &yy2[i], &p[i]); ^