Compilare: main.cpp: In function 'int main()': main.cpp:5:86: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cmcm.in","r",stdin),freopen("cmcm.out","w",stdout),scanf("%d%d%d",&n,&m,&k); ^ main.cpp:5:86: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] main.cpp:5:86: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] main.cpp:7:93: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",a+i,b+i,&z),c[a[i]][b[i]+n+1]=1,v[a[i]][b[i]+n+1]=z,v[b[i]+n+1][a[i]]=-z; ^