uva10405 Longest Common Subsequence（最长公共序列）

标题就说明了方法 。。 典型的dp

 

题目：

Problem C: Longest Common Subsequence

Sequence 1:

Sequence 2:


Given two sequences of characters, print the length of the longest common subsequence of both sequences. For example, the longest common subsequence of the following two sequences:

abcdgh
aedfhr

is adh of length 3.

Input consists of pairs of lines. The first line of a pair contains the first string and the second line contains the second string. Each string is on a separate line and consists of at most 1,000 characters

For each subsequent pair of input lines, output a line containing one integer number which satisfies the criteria stated above.

Sample input

a1b2c3d4e
zz1yy2xx3ww4vv
abcdgh
aedfhr
abcdefghijklmnopqrstuvwxyz
a0b0c0d0e0f0g0h0i0j0k0l0m0n0o0p0q0r0s0t0u0v0w0x0y0z0
abcdefghijklmnzyxwvutsrqpo
opqrstuvwxyzabcdefghijklmn

Output for the sample input

4
3
26
14


代码：

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;

char str1[2000];
char str2[2000];
int d[2000][2000];
int main()
{
    while(gets(str1))
    {
        gets(str2);
        int len1= strlen(str1);
        int len2= strlen(str2);

        for(int i=1;i<=len1;i++)
        {
            for(int j=1;j<=len2;j++)
            {
                if(str1[i-1]== str2[j-1])
                {
                    d[i][j]  = d[i-1][j-1]+1;
                }
                else
                {
                    d[i][j] = max (d[i-1][j],d[i][j-1]);
                }
            }

        }
        cout<<d[len1][len2]<<endl;
        memset(d,0,sizeof(d));
    }


    return 0;
}