Compilare: main.c: In function 'main': main.c:5:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("dreptunghi.in","r",stdin),freopen("dreptunghi.out","w",stdout),scanf("%d%d",&n,&m); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:5:40: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("dreptunghi.in","r",stdin),freopen("dreptunghi.out","w",stdout),scanf("%d%d",&n,&m); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:5:77: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] freopen("dreptunghi.in","r",stdin),freopen("dreptunghi.out","w",stdout),scanf("%d%d",&n,&m); ^~~~~~~~~~~~~~~~~~~