青蛙换位问题，左边的青蛙和右边的青蛙要面对面跳跃，墩子数比青蛙数多1，左边右边交换位置了代表成功-Frog problem of transposition, the frog on the left and right sides of the frog to jump face to face baidunzi than frog a few more than a left right swap positions on behalf of successful