不是說return -1等同于return index，你再看一下，else語句塊中，已經(jīng)令index=-1了，所以這時(shí)候，return -1=return index ，其實(shí)index沒啥用，完全可以替換成?

else?
{
????return?-1;
}

#include <stdio.h>
#define N 10
int main()
{
?
??? int score[N]={67,98,75,63,82,79,81,91,66,84};
??? int sum=0,max,min,i,t,k,s;
??? for(i=0;i<10;i++)
??? printf("%4d",score[i]);
??? printf("\n\n");
??? for(i=0;i<10;i++)
??? {
??? ?sum=sum+score[i];
??? ?}
??? printf("總分?jǐn)?shù)%d\n",sum);
??? printf("平均分%d\n",sum/10);
??? max=score[0];min=score[0];
??? for(i=0;i<10;i++)
??? {
??? ?if(score[i]>max)??? max=score[i];
??? ?if(score[i]<min)??? min=score[i];
??}
??printf("最高分?jǐn)?shù)%d\n",max);
??printf("最低分?jǐn)?shù)%d\n",min);
??for(i=0;i<10;i++)
??{
????? t=i;
???for(k=i+1;k<10;k++)?
???if(score[t]>score[k])? t=k;
???s=score[i];score[i]=score[t];score[t]=s;
??}
??printf("從低到高的分?jǐn)?shù)排列:\n");
??for(t=0;t<10;t++)
??printf("%4d",score[t]);
??? return 0;
}