Compilare: main.cpp: In function 'int main()': main.cpp:41:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<panamea[v[i].y].size(); j++){ ~^~~~~~~~~~~~~~~~~~~~~~~ main.cpp:32:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("tester.in", "r", stdin); ^ main.cpp:33:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("tester.out", "w", stdout); ^ main.cpp:35:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:37:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &v[i].x, &v[i].y); ^