蓝桥杯2015年第六届真题-切开字符串

解题思路:

注意事项:

参考代码:

#include<iostream>
#include<string>
#include<set>
using namespace std;
string s1;
int ish(int n)
{
    set<string> s;
    for(int i=0;i<n;i++)
    {
        s.insert(s1.substr(i,1));
    }
    if(n>1)
    {
        for(int i=2;i<n;i+=2)
        {
            for(int j=0;j+i<n;j++)
            {
                int k=i+j;
                for(int h=j;h<i/2+j;h++)
                {
                    if(s1[h]==s1[k--])
                    {
                        if(h+1 == k)
                        {
                            s.insert(s1.substr(j,i+1));
                        }
                        continue;
                    }
                    else
                    {
                        break;
                    }
                }
            }
        }
    }
    // for(set<string>::iterator it=s.begin();it!=s.end();it++)
    // {
    //     cout<<*it<<endl;
    // }
    return s.size();
}

int noh(int x)
{
    set<string> s;
    if(s1.size()-x == 1)
    {
        return 0;
    }
    for(int i=2;i<=s1.size()-x;i++)
    {
        for(int j=x;j<=s1.size()-i;j++)
        {
            int k=j+i-1;
            for(int h=j;h<s1.size();h++)
            {
                if(s1[h]==s1[k--])
                {
                    if(h+1 == k)
                    {
                        break;
                    }
                    else if(h == k)
                    {
                        s.insert(s1.substr(j,i));
                        break;
                    }
                }
                else
                {
                    s.insert(s1.substr(j,i));
                    break;
                }
            }
        }
    }
    // for(set<string>::iterator it=s.begin();it!=s.end();it++)
    // {
    //     cout<<*it<<endl;
    // }
    return s.size();
}

int main()
{
    int n;
    int sum=-1;
    cin>>n>>s1;
    for(int i=1;i<n;i++)
    {
        int s=ish(i)*noh(i);
        if(s>sum)
        {
            sum=s;
        }
    }
    cout<<sum<<endl;
    return 0;
}