Compilare: main.cpp: In function 'int main()': main.cpp:118:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 1; j < nodes[i].size() ; ++j){ ~~^~~~~~~~~~~~~~~~~ main.cpp:86:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("kdist.in", "r", stdin); ^ main.cpp:87:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("kdist.out", "w", stdout); ^ main.cpp:89:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ main.cpp:92:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ main.cpp:102:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &cul); ^