func_code_string: #include<iostream>   #include<bits/stdc++.h>   using namespace std;   typedef long long int ll;   ll max(ll a,ll b){       if(a>b)return a;       return b;   }   int main(){       int T;       cin>>T;       while(T--){           int n,k;           cin>>n>>k;           string s1,s2;           cin>>s1;           cin>>s2;           vector<int>c1(26,0),c2(26,0);           for(int i=0;i<s1.length();i++){               c1[s1[i]- a ]++;           }           for(int i=0;i<s2.length();i++){               c2[s2[i]- a ]++;           }           for(int i=0;i<26;i++){               if(c1[i]==c2[i]){                  c1[i]=0;                  c2[i]=0;               }               else if(c1[i]<c2[i]){                   c2[i]-=c1[i];                   c1[i]=0;               }               else{                   c1[i]-=c2[i];                   c2[i]=0;               }           }           int f=0;           int j=25;int i=25;           while(j>=0 && i>=0){               if(c1[i]==0){                  i--;                  continue;               }               if(c2[j]==0){                  j--;                  continue;               }               if(i>j){                  f=1;                  break;               }                         if(c1[i]%k!=0){                  f=1;                  break;              }               if(c2[j]%k!=0){                  f=1;                  break;               }               if(c1[i]==c2[j]){                  c1[i]=0;                  c2[j]=0;                  i--;                  j--;                                 }               else if(c1[i]>c2[j]){                  c1[i]-=c2[j];                  j--;               }               else{                  c2[j]-=c1[i];                  i--;               }           }           if(f==1)           cout<< NO <<endl;           else           cout<< YES <<endl;       }   }   