Compilare: user.cpp: In function ‘int solve(std::vector<std::pair<int, int> >)’: user.cpp:61:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 1 ; i <= v.size() ; ++i) ^ user.cpp:69:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 1 ; i < v.size() ; ++i) ^ user.cpp: In function ‘int main()’: user.cpp:89:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("carpetbomber.in", "r", stdin); ^ user.cpp:90:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("carpetbomber.out", "w", stdout); ^ user.cpp:92:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:96:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &type, &X, &Y); ^