Codechef April Challenge 2014, Long Contest BINTREE - "Shortest Path in Binary Trees" solution

Codechef April Challenge 2014, Long Contest BINTREE - "Shortest Path in Binary Trees": http://www.codechef.com/APRIL14/problems/BINTREE

Codechef April Challenge 2014, Long Contest BINTREE - "Shortest Path in Binary Trees" editorial: http://discuss.codechef.com/questions/41181/bintree-editorial

Codechef April Challenge 2014, Long Contest BINTREE - "Shortest Path in Binary Trees" solution:

#include <iostream>
#include <cstdio>
using namespace std;

int main() {
    int n, same, i_st, j_st, c;
    long long int i, j, a[35], b[35], depth[35];
    depth[0]=1;
    for(int m=1; m<33; m++) depth[m]=depth[m-1]<<1;
    scanf("%d", &n);
    while(n--) {
        for(int m=0; m<35; m++) a[m]=b[m]=0;
        i_st=j_st=same=0;
        scanf("%lld%lld", &i, &j);
        c=0;
        while(i>=depth[c]) c++;
        for(int m=c-1; m>=0; m--) a[m]=i, i=i>>1;
        i_st=c;
        c=0; 
        while(j>=depth[c]) c++;
        for(int m=c-1; m>=0; m--) b[m]=j, j=j>>1;
        j_st=c;
        for(int m=0; m<33; m++) if(a[m]!=b[m] || a[m]==0 || b[m]==0) { same=m; break; }
        printf("%d\n", i_st+j_st-2*same);
    }
    return 0;
}