zoukankan      html  css  js  c++  java
  • Unique Paths ——LeetCode

    A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).

    The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish' in the diagram below).

    How many possible unique paths are there?

    Above is a 3 x 7 grid. How many possible unique paths are there?

    Note: m and n will be at most 100.

    题目大意:给定一个棋盘,从左上走到右下,一步走一个格,只能往右或往下走,问有多少种不同的走法。

    解题思路:简单的动规,递推公式F(i,j)=F(i-1,j)+F(i,j-1),初始值F(0,0)=1。

    public class Solution {
        public int uniquePaths(int m, int n) {
            int[][] cnt = new int[m][n];
            cnt[0][0]=1;
            for(int i=0;i<m;i++){
                for(int j=0;j<n;j++){
                    if(i==0&&j==0)
                        continue;
                    if(i==0&&j!=0){
                        cnt[i][j]=cnt[i][j-1];
                    }
                    else if(j==0&&i!=0){
                        cnt[i][j]=cnt[i-1][j];
                    } else {
                        cnt[i][j]=cnt[i-1][j]+cnt[i][j-1];
                    }
                }
            }
            return cnt[m-1][n-1];
        }
    }
  • 相关阅读:
    CSP游戏 4
    CSP 交通规划
    CSP 地铁修建
    CSP 通信网络
    CSP URL映射
    CSP 权限查询
    CSP Markdown
    CSP JSON 查询
    SQL里的子查询
    SQL里的操作符
  • 原文地址:https://www.cnblogs.com/aboutblank/p/4599776.html
Copyright © 2011-2022 走看看