程序代码：

#include <stdio.h>
#include <conio.h>
main()
{
        int  n, m;
        long  sum;
        sum=0;
        printf("\nInput n,m\n");
        scanf("%d,%d", &n, &m);
        while (n <= m)
        {
                sum=sum+n;
                n++;
        }
        printf("sum=%ld\n", sum);
}