UVA 11552 Fewest Flops

#include<cstdio>
#include<iostream>
#include<cstring>
#include<algorithm>
#define MAX 1100
using namespace std;

char s[MAX];
int L,k,dp[MAX][26],count_t[26];

void init(){
cin>>k;
cin>>s;
L=strlen(s);
memset(dp,0x7f,sizeof(dp));
}

void solve(){
for(int i=0;i<L/k;i++){
int front=i*k,rear=(i+1)*k-1;
memset(count_t,0,sizeof(count_t));
for(int j=front;j<=rear;j++)
count_t[s[j]-'a']++;
int kind=0;
for(int j=0;j<26;j++)
if(count_t[j])
kind++;
for(int j=0;j<26;j++){
if(count_t[j]){
if(i==0)
dp[i][j]=kind;
else{
for(int t=0;t<26;t++){
if(j!=t){
if(count_t[t])
dp[i][j]=min(dp[i][j],dp[i-1][t]+kind-1);
else
dp[i][j]=min(dp[i][j],dp[i-1][t]+kind);
}
else{
if(kind==1)
dp[i][j]=min(dp[i][j],dp[i-1][t]);
else
dp[i][j]=min(dp[i][j],dp[i-1][t]+kind);
}
}
}
}
}
}
int ans=0x7f7f7f7f;
for(int i=0;i<26;i++){
ans=min(ans,dp[L/k-1][i]);
}
cout<<ans<<endl;
}

int main(){
int T;
cin>>T;
while(T--){
init();
solve();
}
return 0;
}