Compilare: main.cpp: In function 'bool bfs(int, int)': main.cpp:25:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<g[u].size(); i++){ ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:55:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<g[102].size(); i++){ ~^~~~~~~~~~~~~~ main.cpp:76:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<sol.size(); i++) ~^~~~~~~~~~~ main.cpp:37:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("ghizi.in", "r", stdin); ^ main.cpp:38:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ghizi.out", "w", stdout); ^ main.cpp:40:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ main.cpp:42:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^