Compilare: user.c: In function ‘Ciur’: user.c:16:13: warning: implicit declaration of function ‘sqrt’ [-Wimplicit-function-declaration] if (i <= sqrt(n)) ^ user.c:16:22: warning: incompatible implicit declaration of built-in function ‘sqrt’ [enabled by default] if (i <= sqrt(n)) ^ user.c: In function ‘main’: user.c:33:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(input, "%d ", &n); ^