#include <iostream>
#include <cstdio>

using namespace std;
int nums[2147483648];
int index(int x){
	int idx=x&1, tmp=x;
	for(;(x=x>>1);){
		if(x & 1){
			idx++;
		}
	}
	nums[tmp]=idx;
	return idx;
}

int cmpIDX(int x, int y){
	int max=0, tmp=0, tmpe=x;
	for(int e=x;e<=y;e++){
		tmp=nums[e]?nums[e]:index(e);
		if(tmp>max){
			max=tmp;
			tmpe=e;
		}
	}
	return tmpe;
}

int main(){
    //freopen("1.in","r",stdin);
    int n, CASE=1;
    cin >> n;
    for(int i = 0; i < n; i++){
        int min,max;
		scanf("%d %d",&min, &max);
        printf("Case %d: %d\n",CASE,cmpIDX(min,max));
        CASE++;
    }
    return 0;
}