Compilare: main.c: In function 'main': main.c:7:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("cifra.in","r",stdin),freopen("cifra.out","w",stdout),scanf("%d\n",&t); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:7:32: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("cifra.in","r",stdin),freopen("cifra.out","w",stdout),scanf("%d\n",&t); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:7:64: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] freopen("cifra.in","r",stdin),freopen("cifra.out","w",stdout),scanf("%d\n",&t); ^~~~~~~~~~~~~~~~ main.c:15:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%s\n",s),m=strlen(s),n=(m>1?((s[m-2]-'0')*10+s[m-1]-'0'):(s[m-1]-'0')),printf("%d\n",v[n]); ^~~~~~~~~~~~~~~