zoukankan      html  css  js  c++  java
  • Common Subsequence HDU 1159 最长公共子序列Longest Common Subsequence,LCS

    A subsequence of a given sequence is the given sequence with some elements (possible none) left out. Given a sequence X = <x1, x2, ..., xm> another sequence Z = <z1, z2, ..., zk> is a subsequence of X if there exists a strictly increasing sequence <i1, i2, ..., ik> of indices of X such that for all j = 1,2,...,k, xij = zj. For example, Z = <a, b, f, c> is a subsequence of X = <a, b, c, f, b, c> with index sequence <1, 2, 4, 6>. Given two sequences X and Y the problem is to find the length of the maximum-length common subsequence of X and Y. 
    The program input is from a text file. Each data set in the file contains two strings representing the given sequences. The sequences are separated by any number of white spaces. The input data are correct. For each set of data the program prints on the standard output the length of the maximum-length common subsequence from the beginning of a separate line. 

    Input

    abcfbc abfcab
    programming contest 
    abcd mnp

    Output

    4
    2
    0
    就一模板
    if Xi=Yi,fnid the LCS of Xi-1 and Yi-1;
    else{
      if(Xi==Yj)L[i][j]=L[i-1][j-1]+1;
      else L[i][j]=max(L[i][j-1],L[i-1][j]);
    }
    还是打伪代码比打字快(逃
    //#include <bits/stdc++.h>
    #include <iostream>
    #include <cstdio>
    #include <cmath>
    #include<cstring>
    #include <algorithm>
    #include <queue>
    #include<map>
    using namespace std;
    typedef long long ll;
    const ll inf = 1e13;
    const int mod = 1000000007;
    const int mx = 1005; //check the limits, dummy
    typedef pair<int, int> pa;
    const double PI = acos(-1);
    ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
    #define swa(a,b) a^=b^=a^=b
    #define re(i,a,b) for(int i=(a),_=(b);i<_;i++)
    #define rb(i,a,b) for(int i=(b),_=(a);i>=_;i--)
    #define clr(a) memset(a, 0, sizeof(a))
    #define lowbit(x) ((x)&(x-1))
    #define mkp make_pai
    //void sc(int& x) { scanf("%d", &x); }void sc(int64_t& x) { scanf("%lld", &x); }void sc(double& x) { scanf("%lf", &x); }void sc(char& x) { scanf(" %c", &x); }void sc(char* x) { scanf("%s", x); }
    int n, m, k,ans[mx];
    int dp[mx][mx];
    string s1, s2;
    int LCS() {
        clr(dp);
        re(i, 1, s1.length()+1)
            re(j, 1, s2.length()+1) {
            if (s1[i - 1] == s2[j - 1])
                dp[i][j] = dp[i - 1][j - 1] + 1;
            else
                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
        }
        return dp[s1.length()][s2.length()];
    }
    int main()
    {
        ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
        while (cin>>s1>>s2)
        {
            cout << LCS() << endl;
        }
        return 0;
    }
  • 相关阅读:
    nginx基础系列
    常用MS-SQL写法整理
    Spring Bean装配方式
    sql获取该周的开始结束日期
    Docker基础入门实践
    vim常规操作
    基于CentOS的SSHD服务的Docker镜像
    RedisClient For .Net
    Redis数据类型及使用场景
    CentOS下安装Redis
  • 原文地址:https://www.cnblogs.com/xxxsans/p/12741507.html
Copyright © 2011-2022 走看看