处理起来稍微有点麻烦

#include<bits/stdc++.h>
using namespace std;
int main() {
    int k;
    string s="";
    cin>>k>>s;
    int hashTable[128]={0};
    for (int i = 0; i < s.size();) {
      int j=i+1;
      while (j<s.size() and s[j]==s[i])
          j++;
      if (hashTable[s[i]]>=0)
          hashTable[s[i]]=(j-i)%k==0?1:-1;
      i=j;
    }
    string outPut="";
    bool hashOut[128]={false};
    for (int i = 0; i < s.size(); ) {
        outPut+=s[i];
        if (hashTable[s[i]]>0){
            if (!hashOut[s[i]]){
                printf("%c",s[i]);
                hashOut[s[i]]= true;
            }
            i+=k;
        }
        else if (hashTable[s[i]]<0){
            i++;
        }
    }
    cout<<endl<<outPut;
}