Eroare de compilare: user.c: In function ‘bun’: user.c:7: error: ‘for’ loop initial declarations are only allowed in C99 mode user.c:7: note: use option -std=c99 or -std=gnu99 to compile your code user.c: In function ‘back’: user.c:31: error: ‘for’ loop initial declarations are only allowed in C99 mode user.c: In function ‘main’: user.c:41: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:42: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:43: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result