Compilare: user.c: In function ‘push’: user.c:24:5: warning: implicit declaration of function ‘size’ [-Wimplicit-function-declaration] if (size(st) == STACK_SIZE) ^ user.c: In function ‘init’: user.c:21:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘main’: user.c:107:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fp_read, "%d", &n); ^