Eroare de compilare: user.c: In function ‘C’: user.c:6:1: warning: implicit declaration of function ‘cmmdc’ [-Wimplicit-function-declaration] long long C(long long a,long long b) { return !b?a:cmmdc(b,a%b); } ^ user.c: In function ‘main’: user.c:8:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("copaci.in","r",stdin),freopen("copaci.out","w",stdout),scanf("%lld",&n); ^ user.c:8:40: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("copaci.in","r",stdin),freopen("copaci.out","w",stdout),scanf("%lld",&n); ^ user.c:8:71: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("copaci.in","r",stdin),freopen("copaci.out","w",stdout),scanf("%lld",&n); ^ user.c:10:11: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%lld",&x[i],&y[i]); ^ /tmp/cctif04g.o: In function `C': user.c:(.text+0x3f): undefined reference to `cmmdc' /tmp/cctif04g.o: In function `main': user.c:(.text.startup+0x37d): undefined reference to `cmmdc' user.c:(.text.startup+0x444): undefined reference to `cmmdc' collect2: error: ld returned 1 exit status