题解 | #编程题2# 滑动窗口+哈希表 C++实现

#include <iostream>
#include <unordered_map>
using namespace std;

int main() {
    int n,m;
    string str;
    cin>>n>>m>>str;
    int l=0;
    int r=1;
    int mxlen = 1;
    unordered_map<char, int> mp; 
    mp[str[0]]=1;
    char other;
    while(r!=str.length())
    {
        mp[str[r]]++;
        if(mp['a']>mp['b'])
        {
            other = 'b';
        }
        else {
            other = 'a';
        }

        while(mp[other]>m)
        {
            mp[str[l]]--;
            l++;
            if(mp['a']>mp['b'])
            {
                other = 'b';
            }
            else {
                other = 'a';
            }
        }
        mxlen = max(mxlen,r-l+1);
        r++;
    }
    cout<<mxlen;
    return 0;
}