Compilare: main.cpp: In function 'void B(int)': main.cpp:18:12: warning: suggest parentheses around assignment used as truth value [-Wparentheses] for(b[i]=j=0,k=v[i].size();j<k;j++) ~^~ main.cpp: In function 'int main()': main.cpp:24:82: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in","r",stdin),freopen("ctc.out","w",stdout),scanf("%d%d",&n,&m); ^ main.cpp:24:82: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] main.cpp:24:82: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] main.cpp:26:61: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y),u[x].push_back(y),v[y].push_back(x); ^