#include "stdio.h.h"
//#include "time.h"
//?????§??????????´???°?????????????????????
// 5<= n <= 10000
//p1=?°????????´???°p2=??§???????´???°

void isprime(int n) {
    scanf("%d",&n);
    for(int i = 2; i < n; i++) {   //??????????§????????????¨??§??¶??°??§??????????´???°??¨??????
        if(n % i == 0)return 0;    //????????????????????§?´???°??§?????????
    }
    return 1;
}


int main(){
    int i,n,p1,q1;
//    clock_t start, now;//??£?¨?
    while(1){
        scanf("%d",&n);
//        start = clock(); // ????§???????
        if(n == 0)break;
        for(i = n;0 <= i;i--){
            if (isprime(i) == 1 && isprime(i-2)) break;
            p1 = i-2;
            q1 = i;
        }
//        now = clock(); // ????????????
//        printf("%f\n", (double)(now - start) / CLOCKS_PER_SEC);//??¬???
        printf("%d %d\n",p1,q1);
    }
}