C + + two fork Tree

/*
Problem: Small ball Drop: There is a binary tree with a maximum depth of D, and all leaves have the same depth. All nodes are numbered from top to bottom, from left to right, all the way to 2^d-1. Place a small ball at node 1 where it will fall,
Each node has a switch, the initial state is all closed, and each time a ball falls on a switch, the state changes. When the ball reaches an inner node, if the switch on the node is closed, go left, or go to the right,
Until you go to the leaf node.
Enter the leaf depth and the number of balls, and output the last leaf node number of the first ball
Solution: For a node, its left child and right child nodes are 2k and 2k+1 respectively.

*/


#include <iostream>
#include <cstdio>
#include <cstring>
using namespace Std;
const int MAXD=20;
int s[1<<maxd];//Maximum number of nodes is 2^maxd-1
int main ()
{
int d,i;
while (scanf ("%d%d", &d,&i) ==2) {
Memset (s,0,sizeof (s));//Switch
int k,n= (1&LT;&LT;D) -1;//n is the maximum node number
for (int i=0;i<i;i++) {//Let I drop a ball continuously
k=1;
for (;;) {
s[k]=!s[k];//the side switch status
k=s[k]?k*2:k*2-1;//three-mesh operator assignment
if (k>n) break;//has fallen "out of Bounds"
}
}
printf ("%d\n", K/2);//leaf number before bounds
}

return 0;
}

C + + two fork Tree