#include <stdio.h>
 
// 入れ替え。配列のi番目とj番目を
void swap(int a[], int i, int j){
	int temp;
	printf("入れ替え発生。%p配列の%d番目と%d番目を入れ替えます。\n", a, i, j );
	temp=a[i];
	a[i]=a[j];
	a[j]=temp;
}
 
// 逆順に配列を並び替え
void reverse(int a[], int n){
	int i;
	for( i=0 ; i<n/2;i++){
		swap( a, i, n-i-1 );
	}
	printf("\n");
}
 
int main(void) {
	int data[4]={4,3,2,1};
	int data2[5]={1,3,5,7,9};
	int data3[6]={1,2,3,4,5,6};
 
	reverse(data, 4);
	reverse(data2, 5);
	reverse(data3, 6);
 
	return 0;
}
 

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