#include <stdio.h>

int main()
{
   
    int a, b;
    scanf("%d%d", &a, &b); 
    float c;
    scanf("%f", &c);
    if (c==a+b)
    printf("OK \n");
    else
    printf("ZLE\n");
    scanf("%d%d", &a, &b);
    scanf("%f", &c);
    if (c==a*b)
    printf("OK \n");
    else
    printf("ZLE\n");
    scanf("%d%d", &a, &b);
    scanf("%f", &c);
    if (c==a/b)
    printf("OK");
    else
    printf("ZLE \n");
    scanf("%d%d", &a, &b);
    scanf("%f", &c);
    if (c==a/b)
    printf("OK \n");
    else
    printf("ZLE \n");
    return 0;
    
    
}