Compilare: user.cpp: In function ‘int main()’: user.cpp:41:91: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("catun.in","r",stdin),freopen("catun.out","w",stdout),scanf("%d%d%d",&n,&m,&l); ^ user.cpp:41:91: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:41:91: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:45:53: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x),d[x]=0,h[++k]=x,p[x]=k,b[x]=x; ^ user.cpp:47:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&z),A(x,y,z),A(y,x,z); ^