Compilare: user.cpp: In function ‘int main()’: user.cpp:54:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<a[val].size(); ++i) ^ user.cpp:60:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<b[val].size(); ++i) ^ user.cpp:32:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("vopsire.in", "r", stdin); ^ user.cpp:33:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("vopsire.out", "w", stdout); ^ user.cpp:35:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &Q); ^ user.cpp:39:47: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &xi, &xf, &yi, &yf); ^ user.cpp:47:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &X, &Y); ^