reverse

#include <iostream>
#include <algorithm>
using namespace std;


void main()
{
int ari[]={1,2,3,4,5,6,7,8,9};
int i;

for (i=0;i<9;i++) printf("%d ",ari[i]);puts("");
reverse(&ari[2],&ari[6]);
for (i=0;i<9;i++) printf("%d ",ari[i]);puts("");
}