#include <stdio.h>
main()
{
    int a,b,c;
    printf("请输入三个整数：");
    scanf("%d%d%d",a,b,c);
    if (a>b)
    {
        if(c>a)
            printf("%d>%d>%d",c,a,b);
            else
        {
            if(c<b)
                printf("%d>%d>%d",a,b,c);
            else
                printf("%d>%d>%d",a,c,b);
        }
    }
    else
    {
        if(c>b)
            printf("%d>%d>%d",c,b,a);
            else
        {
            if(c<a)
                printf("%d>%d>%d",b,a,c);
                else
                printf("%d>%d>%d",b,c,a);
        }
    }
}

#include <stdio.h>
main()
{
    int a,b,c;
    printf("请输入三个整数：");
    scanf("%d%d%d",&a,&b,&c);
    if (a>b)
    {
        if(c>a)
            printf("%d>%d>%d",c,a,b);
            else
        {
            if(c<b)
                printf("%d>%d>%d",a,b,c);
            else
                printf("%d>%d>%d",a,c,b);
        }
    }
    else
    {
        if(c>b)
            printf("%d>%d>%d",c,b,a);
            else
        {
            if(c<a)
                printf("%d>%d>%d",b,a,c);
                else
                printf("%d>%d>%d",b,c,a);
        }
    }
}

#include <stdio.h>
int main()
{
    int a=0,b=0,c=0;
    printf("请输入三个整数：");
    scanf("%d%d%d",&a,&b,&c);//scanf()函数你要仔细看看，细心点就好了，而且变量在用的时候最好先初始化
    if (a>b)
    {
        if(c>a)
            printf("%d>%d>%d",c,a,b);
        else
        {
            if(c<b)
                printf("%d>%d>%d",a,b,c);
            else
                printf("%d>%d>%d",a,c,b);
        }
    }
    else
    {
        if(c>b)
            printf("%d>%d>%d",c,b,a);
        else
        {
            if(c<a)
                printf("%d>%d>%d",b,a,c);
            else
                printf("%d>%d>%d",b,c,a);
        }
    }
    return 0;
} 

书没看透！不要急于发问！