Compilare: user.cpp: In function ‘int main()’: user.cpp:38:21: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if (i&(1<<j)!=0) { ^ user.cpp:39:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k=0;k<g[j].size();k++) ^ user.cpp:43:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<g[0].size();i++) ^ user.cpp:24:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hamilton.in","r",stdin); ^ user.cpp:25:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hamilton.out","w",stdout); ^ user.cpp:26:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); maxx=1<<n; ^ user.cpp:29:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&z); ^