#include <stdio.h>
#include <stdlib.h>
int main()
{
    int a,b,n,j,N;
    scanf("%d",&N);
    for(n=0;n<=1000000000000;n++){
		if(N<=(n+1)*n/2){
			break;
		}
    }
	j=n-1;
    a=N-j*(j+1)/2;
    b=n+1-a;
    printf("%d/%d",a,b);
	
    
    return 0;
}