第九周程序改错

#include  <stdio.h>
#define ARR_SIZE 10
void  MaxMinExchang(int *a, int n);//加了函数声明 
int main() {
    int a[ARR_SIZE], i, n;
    printf("Input n(n<=10):
");
    scanf("%d", &n);
    printf("Input %d Numbers:
", n);
    for (i=0; i<n; i++) {
        scanf("%d", &a[i]);
    }
    MaxMinExchang(a, n);
    printf("After MaxMinExchange:
");
    for (i=0; i<n; i++) {
        printf("%d ", a[i]);
    }
    printf("
");
    return 0;
}
void  MaxMinExchang(int *a, int n) {
    int  maxValue = a[0], minValue = a[0], maxPos=0, minPos=0;//给了初值 
    int  i, temp;
    for (i=0; i<n; i++) {
        if (a[i] > maxValue) {
            maxValue = a[i];
            maxPos = i;
        }
        if (a[i] < minValue) {
            minValue = a[i];
            minPos = i;
        }
    }
    temp = a[maxPos];
    a[maxPos] = a[minPos];
    a[minPos] = temp;
}