面试宝典——求一个字符串中连续出现次数最多的子串

#include"iostream"
#include"stdio.h"
#include"string.h"
#include"vector"
using namespace std;

const int MAXN=100005;

pair<int,string> fun(const string &str)
{
    vector<string>subs;
    int maxcount=1,count=1;
    string substr;
    int i,len=str.length();
    for(i=0;i<len;i++)
    {
        subs.push_back(str.substr(i,len-i));
    }
    for(i=0;i<len;i++)
    {
        for(int j=i+1;j<=(len+i)/2;j++)
        {
                count=1;
                if(subs[i].substr(0,j-i)==subs[j].substr(0,j-i))
                {
                    count++;
                    for(int k=j+(j-i);k<len;k+=j-i)
                    {
                        if(subs[i].substr(0,j-i)==subs[k].substr(0,j-i))
                            count++;
                        else
                            break;
                    }
                    if(count>maxcount)
                    {
                        maxcount=count;
                    }
                }
        }
    }
    return make_pair(maxcount,substr);
}

pair<int,string> fun1(const string& str)
{
    int maxcount=1,count=1;
    string substr;
    int i=0,j=0;
    int len=str.length();
    int k=i+1;
    while(i<len)
    {
        j=str.find(str[i],k);
        if(j==string::npos || j>(len+i)/2)
        {
            i++;
            k=i+1;
        }
        else
        {
            int s=i;
            int s1=j-i;
            while(str.substr(s,s1)==str.substr(j,s1))
            {
                count++;
                s=j;
                j=j+s1;
            }
            if(count>maxcount)
            {
                maxcount=count;
                substr=str.substr(i,s1);
            }
            k=j+1;
            count=1;
        }
    }
    return make_pair(maxcount,substr);
}

int main()
{
    string str;
    pair<int,string> rs;
    while(cin>>str)
    {
        rs=fun(str);
        cout<<rs.second<<":"<<rs.first<<endl;
        rs=fun1(str);
        cout<<rs.second<<":"<<rs.first<<endl;
    }
    return 0;
}