CF 25 E 三个字符串 KMP模板

Time Limit: 2000MS   Memory Limit: 262144KB   64bit IO Format: %I64d & %I64u

 Status

Description

Sometimes it is hard to prepare tests for programming problems. Now Bob is preparing tests to new problem about strings — input data to his problem is one string. Bob has 3 wrong solutions to this problem. The first gives the wrong answer if the input data contains the substring s1, the second enters an infinite loop if the input data contains the substring s2, and the third requires too much memory if the input data contains the substring s3. Bob wants these solutions to fail single test. What is the minimal length of test, which couldn't be passed by all three Bob's solutions?

Input

There are exactly 3 lines in the input data. The i-th line contains string si. All the strings are non-empty, consists of lowercase Latin letters, the length of each string doesn't exceed 105.

Output

Output one number — what is minimal length of the string, containing s1s2 and s3 as substrings.

Sample Input

Input
ab
bc
cd
Output
4
Input
abacaba
abaaba
x
Output
11

Source

题意:将3个字符串连接起来,重复的可以重叠不用计算,输出最短的长度
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
const int maxn = 100000+20;
char s[4][maxn];
int next[4][maxn],len[5];

void get_next(int i)
{
    int k=-1,j=0;
    next[i][0]=-1;
    while(j<len[i])
       if(k==-1||s[i][j]==s[i][k])
         {
            k++;
            j++;
            next[i][j]=k;
         }
       else k=next[i][k];
}

int kmp(int a,int b)
{
     int  i=0,j=0;
     while(j<len[b]&&i<len[a])
     if(i==-1||s[a][i]==s[b][j])
        {
            i++;j++;
        }
     else i=next[a][i];
     return i;
}

int main()
{
    while(~scanf("%s %s %s",s[0],s[1],s[2]))
    {
        int ans=0;
        len[0]=strlen(s[0]);
        len[1]=strlen(s[1]);
        len[2]=strlen(s[2]);
        for(int i=0;i<3;i++) get_next(i);

        for(int i=0;i<3;i++)
          for(int j=0;j<3;j++)
              {
                  if(i==j) continue;
                  for(int k=0;k<3;k++)
                  {
                      if(k==i||k==j) continue;
                      int x=kmp(i,j);
                      int y1=kmp(k,i);
                      int y2=kmp(k,j);
                      ans=max(ans,max(x+y1,x+y2));
                  }
              }
        printf("%d
",len[0]+len[1]+len[2]-ans);
    }
    return 0;
}

  分析:只要求出三个字符串所能得到的最大匹配数就好,

原文地址:https://www.cnblogs.com/smilesundream/p/5552088.html