#include <stdio.h>
int sum(int,int);
int main(void)
{
    int min,max;
    printf("Enter lower and upper integer limits:");
    scanf("%d%d",&min,&max);
    while (min!=max)
         {
             printf("The sums of the squares from %d to %d is %d\n",sum(min,max));
             printf("Enter lower and upper integer limits:");        
             scanf("%d%d",&min,&max);   
         }
         
    printf("Done");
    return 0;
}
int sum(int min,int max)
{
    int  x,y=0;
    for (x = min;x < max;x++)
        y+=x*x;
    return y;
} /*第九题，整了好久都没懂，那个函数怎么调用呐？*/

下次不要贴图，好好看书，题中明明写的是“直到……等于或小于”，而你的代码while (min!=max)中只有是否相等的比较。
其它，都是小错误了

#include <stdio.h>

int sum( int lower, int upper );

int main( void )
{
    for( int lower,upper;
        printf("%s","Enter lower and upper integer limits: ")>0
        && scanf("%d%d",&lower,&upper)==2
        && lower<upper; )
    {
        printf( "The sums of the squares from %d to %d is %d\n", lower*lower, upper*upper, sum(lower,upper) );
    }
    puts( "Done" );

    return 0;
}
int sum( int lower, int upper )
{
    int sum = 0;
    for( ; lower<=upper; ++lower )
        sum += lower*lower;
    return sum;
}

就是while后面的条件错误，函数调用没问题。

嗯嗯，非常感谢！

嗯嗯，谢谢！