B题求助
#include <bits/stdc++.h>
using namespace std;
int lll[26];
int main()
{
int t,k,num=0,ans=50***00;
string s;
int d;
cin>>t;
for(int p=0;p<t;p++)
{
cin>>s>>k;
ans=50***00;
memset(lll,0,sizeof lll);
int l=s.length();
for(int i=0;i<l;i++)
{
lll[s[i]-'a']++;
if(lll[s[i]-'a']>=k)
{
d=lll[s[i]-'a']-k;
for (int j = 0; j < 26; j++) {
if (s[j] == s[i]) {
num = abs(i - j+1);
ans=min(num,ans);
if(d==0)
break;
else d--;
}
}
}
}
if(ans==50***00)
cout<<"-1\n";
else
cout<<ans<<endl;
}
} 