617A

#include <stdio.h>

int main()
{
    int moves[5]={1,2,3,4,5};
    int x;
    scanf("%d", &x);
    int ind=4;
    int Minsteps=0;
    while((x!=0)&&(ind>=0))
    {
        if(x>=moves[ind])
            Minsteps+=x/moves[ind];
        x%=moves[ind--];
    }
    printf("%d\n", Minsteps);
    return 0;
}