Compilare: main.c: In function 'main': main.c:6:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("swaps2.in","r",stdin),freopen("swaps2.out","w",stdout),scanf("%d%s",&n,s); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:6:36: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("swaps2.in","r",stdin),freopen("swaps2.out","w",stdout),scanf("%d%s",&n,s); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:6:69: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] freopen("swaps2.in","r",stdin),freopen("swaps2.out","w",stdout),scanf("%d%s",&n,s); ^~~~~~~~~~~~~~~~~~