Compilare: user.cpp: In function ‘int main()’: user.cpp:7:85: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("petrica.in","r",stdin),freopen("petrica.out","w",stdout),scanf("%d",&n); ^ user.cpp:7:85: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:7:85: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:9:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",s+i),h[i]=n+1; ^ user.cpp:11:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&j,&k),g[j][w[j]++]=k,g[k][w[k]++]=j; ^