Compilare: user.c: In function ‘main’: user.c:18:13: warning: implicit declaration of function ‘atan2’ [-Wimplicit-function-declaration] g=atan2(x[i]-x[c],y[i]-y[c]); ^ user.c:18:15: warning: incompatible implicit declaration of built-in function ‘atan2’ [enabled by default] g=atan2(x[i]-x[c],y[i]-y[c]); ^ user.c:27:11: warning: incompatible implicit declaration of built-in function ‘atan2’ [enabled by default] l=atan2(x[o]-x[c],y[o]-y[c]); ^ user.c:6:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoare.in","r",stdin),freopen("infasuratoare.out","w",stdout),scanf("%d",&n),x[0]=y[0]=1000000000; ^ user.c:6:50: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoare.in","r",stdin),freopen("infasuratoare.out","w",stdout),scanf("%d",&n),x[0]=y[0]=1000000000; ^ user.c:6:88: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoare.in","r",stdin),freopen("infasuratoare.out","w",stdout),scanf("%d",&n),x[0]=y[0]=1000000000; ^ user.c:8:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf%lf",&x[i],&y[i]); ^