Compilare: user.c: In function ‘main’: user.c:16:5: warning: implicit declaration of function ‘isdigit’ [-Wimplicit-function-declaration] if(isdigit(ch)){ ^ user.c:12:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(file1, "%d", &X); ^ user.c:13:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(file1, "%d", &Y); ^