HMMT 二月 2001 · 冲刺赛 · 第 16 题
HMMT February 2001 — Guts Round — Problem 16
题目详情
英文原题
- [6] After walking so much that his feet get really tired, the beaver staggers so that,
at each step, his coordinates change by either (+1 , +1) or (+1 , − 1). Now he walks from
(0 , 0) to (8 , 0) without ever going below the x -axis. How many such paths are there?
解析
英文解析
- [6] After walking so much that his feet get really tired, the beaver staggers so that,
at each step, his coordinates change by either (+1 , +1) or (+1 , − 1). Now he walks from
(0 , 0) to (8 , 0) without ever going below the x -axis. How many such paths are there?
Solution: C (4) = 14 .