Compilare: main.cpp: In function 'void res(int&)': main.cpp:19:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = n; i < me.size(); i++) ve[me[i]] = 0; ~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:42:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v.size(); i++) ~~^~~~~~~~~~ main.cpp:25:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("rays.in", "r", stdin); ^ main.cpp:26:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("rays.out", "w", stdout); ^ main.cpp:29:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:32:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &x, &y1, &y2); ^