#include <stdio.h>
#include <cstdlib>
rec();
main() 
{
    int a, fact;
    char q, n, y;
    printf("\nEnter any number ");
    scanf("%d", & a);
    fact = rec(a);
    printf("Factorial value = %d\n", fact);
    printf("do you want to exit.....(y/n):");
    scanf("%s" ,&q);
    if (q == 'n')
    {
        system("cls");
        main();
    }
    else
        return 0;
}
rec(int x) 
{
    int f;
    if (x == 1) 
        return 1;
    else 
        f = x * rec(x - 1);
    return f;
}
我正在使用代码块,但我不知道如何清除屏幕。我搜索然后system("cls");在头文件中找到#include<cstdlib>,但它显示错误cstdlib: no such file of directory。我该怎么办 ?