Compilare: user.cpp: In function ‘void prim()’: user.cpp:35:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < graf[1].size(); ++i) ^ user.cpp:44:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < graf[curr->y].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:66:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < result.size(); ++i) { ^ user.cpp:50:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in", "r", stdin); ^ user.cpp:51:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out", "w", stdout); ^ user.cpp:55:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:57:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &x, &y, &c); ^