Compilare: user.c: In function ‘main’: user.c:47:19: warning: unused variable ‘i’ [-Wunused-variable] int N, a,b,c, P, i; ^ user.c:47:13: warning: unused variable ‘c’ [-Wunused-variable] int N, a,b,c, P, i; ^ user.c:47:11: warning: unused variable ‘b’ [-Wunused-variable] int N, a,b,c, P, i; ^ user.c:47:9: warning: unused variable ‘a’ [-Wunused-variable] int N, a,b,c, P, i; ^ user.c:48:8: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d", &N, &P); ^