#include"stdio.h"
void main()
{
    int zongshu=0,zimushu=0,shuzishu=0,kongge=0;
    char c;

    while((c=getchar())!='\n')
    {
        zongshu+=1;
        
        if(c>='0'&&c<='9')
        {
            shuzishu+=1;
        }

        if(c>='A'&&c<'Z'||c>='a'&&c<='z')
        {
            zimushu+=1;
        }

        if(c==' ')
        {
            kongge+=1;
        }
    }

    printf("总数=%d\n数字数=%d\n字母数=%d\n空格数=%d\n",zongshu,shuzishu,zimushu,kongge);

}
以上程序当中的  （c=getchar()）为什么不能用scanf("%C",&C)或（c=scanf("%C",&C)）来代替，程序不能正常运行？

好像有点小难，学习了，感谢