【POJ1226】Substrings

来源：Substrings

思路：串（下载）C++字符串函数大全（下载）

代码：

#include <iostream>
#include <string.h>
using namespace std;
#define MAX 101

int t,n;
char str[100][MAX];
char minStr[MAX];

void Init()
{
    int minLen=MAX;
    cin >> n;
    for( int i=0;i<n;i++ )
    {
        cin >> str[i];
        if( strlen(str[i]) < minLen )
        {
            minLen = strlen(str[i]);
            strcpy(minStr,str[i]);
        }
    }
}

//貌似poj不支持strrev，只好自己定义
void strrev(char *revStr,char *str)
{
    int len = strlen(str);
    for( int i=len-1;i>=0;i-- )
    {
        revStr[len-i-1]=str[i];
    }
    revStr[len] = '\0'; 
}

int MaxSubstring()
{
    int sourceLen = strlen(minStr);
    int subStrLen = strlen(minStr);
    char subStr[MAX],revSubStr[MAX];
    bool found;

    while( subStrLen )
    {
        for( int i=0;i<=sourceLen-subStrLen;i++ )
        {
            found=true;
            strncpy(subStr,minStr+i,subStrLen);
            //strncpy(revSubStr,minStr+i,subStrLen);
            subStr[subStrLen] = '\0';
            //revSubStr[subStrLen] = '\0';
            strrev(revSubStr,subStr); 

            for( int j=0;j<n;j++ )
            {
                if( strstr(str[j],subStr) == NULL && strstr(str[j],revSubStr) 

== NULL )
                {
                    found = false;
                    break;
                }
            }
            if( found )
                return subStrLen;
        }
        subStrLen--;
    }

    return subStrLen;
}



int main()
{
    int len;
    cin >> t;
    while(t--)
    {
        Init();
        len = MaxSubstring();
        cout << len << endl;
    }
    return 0;
}