UVa 679

there is an interesting regular pattern here
for depth 1, the left-right cycle is two balls
for depth 2, the cycle is 4 balls
...
for depth k, the cycle is 1<<k balls
and the branch condition, i%2?goleft:goright won't change forever

/* UVas */
/*****************************************************************************/
int n, D, I;
int main(void) {
    cin>>n;
    while(n--) {
        cin>>D>>I;
        int k=1;
        for (int i=1; i<D; i++) {
            if (I%2) {
                I=(I+1)/2;
                k*=2;
            } else {
                I/=2;
                k=k*2+1;
            }
        }
        cout<<k<<endl;
    }
    return 0;
}
/*****************************************************************************/