#include<iostream>
#include<cstring>
#include<cstdlib>
#include<cstdio>
#include<algorithm>
#define ll long long
using namespace std;
const int maxn=500010, inf=1e9;
int n, T, Q, l, r;
int sum[maxn][26];
char s[maxn];

template<typename T>
inline void read(T &k)
{
    int f=1; k=0; char c=getchar();
    while(c<'0' || c>'9') c=='-'&&(f=-1), c=getchar();
    while(c<='9' && c>='0') k=k*10+c-'0', c=getchar();
    k*=f;    
}

int main()
{
    read(T); int cnt=0;
    while(T--)
    {
        cnt++; printf("Case #%d:\n", cnt);
        read(n); read(Q);
        scanf("%s", s+1);
        for(int i=1;i<=n;i++)
        {
            for(int j=0;j<26;j++)
            sum[i][j]=sum[i-1][j]+(s[i]=='A'+j);
        }
        while(Q--)
        {
            read(l); read(r);
            for(int i=0;i<26;i++)
            if(sum[r][i]-sum[l-1][i])
            {
                printf("%d\n", sum[r][i]-sum[l-1][i]);
                break;
            }
        }
    }
}