// Original Python3 code (must be included according to AtCoder rules)
/*
from bisect import*
n,q=map(int,input().split())
s=input()
e=[]
for i in range(1000):
  if i%8==0 and'0'not in str(i):
    e+=[*str(i)],
idx={}
for i in'123456789':
  idx[i]=[]
for i in range(n):
  idx[s[i]]+=i,
INF=1<<60
bs=[-1]*10
for _ in range(q):
  l,r=map(int,input().split())
  l-=1
  d=r-l
  m=min(d,3)
  ans=INF
  for i in range(1,10):
    bs[i]=bisect(idx[str(i)],r-1)-1
  for st in e:
    if m!=len(st):
      continue
    p={}
    a=0
    pos=r-1
    mv=[]
    for j in range(m):
      ns=st[~j]
      k=bs[int(ns)]
      if ns not in p:
        p[ns]=0
      if 0<=k-p[ns]<len(idx[ns])and l<=idx[ns][k-p[ns]]:
        nxt=idx[ns][k-p[ns]]
        for t in mv:
          if t<idx[ns][k-p[ns]]:
            nxt-=1
        a+=abs(pos-nxt)
        mv+=idx[ns][k-p[ns]],
        p[ns]+=1
      else:
        a=INF
        break
      pos-=1
    ans=min(ans,a)
  print([-1,ans][ans<INF])
*/

#include <bits/stdc++.h>
using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, q;
    cin >> n >> q;
    string s;
    cin >> s;

    vector<string> e;
    for (int i = 0; i < 1000; i++) {
        if (i % 8 == 0) {
            string t = to_string(i);
            if (t.find('0') == string::npos) {
                string tmp = "";
                for (char c : t) tmp.push_back(c);
                e.push_back(tmp);
            }
        }
    }

    unordered_map<char, vector<int>> idx;
    for (char c = '1'; c <= '9'; c++) idx[c] = {};
    for (int i = 0; i < n; i++) {
        idx[s[i]].push_back(i);
    }

    const long long INF = 1LL << 60;
    vector<int> bs(10, -1);

    while (q--) {
        int l, r;
        cin >> l >> r;
        l -= 1;
        int d = r - l;
        int m = min(d, 3);
        long long ans = INF;

        for (int i = 1; i <= 9; i++) {
            auto &vec = idx['0' + i];
            auto it = upper_bound(vec.begin(), vec.end(), r - 1);
            bs[i] = int(it - vec.begin()) - 1;
        }

        for (auto &st : e) {
            if (m != (int)st.size()) continue;
            unordered_map<char, int> p;
            long long a = 0;
            int pos = r - 1;
            vector<int> mv;
            bool ok = true;
            for (int j = 0; j < m; j++) {
                char ns = st[m - 1 - j]; // st[~j] in Python
                int k = bs[ns - '0'];
                if (!p.count(ns)) p[ns] = 0;
                int idxpos = k - p[ns];
                if (0 <= idxpos && idxpos < (int)idx[ns].size() && l <= idx[ns][idxpos]) {
                    int nxt = idx[ns][idxpos];
                    for (int t : mv) {
                        if (t < idx[ns][idxpos]) nxt -= 1;
                    }
                    a += abs(pos - nxt);
                    mv.push_back(idx[ns][idxpos]);
                    p[ns] += 1;
                } else {
                    a = INF;
                    ok = false;
                    break;
                }
                pos -= 1;
            }
            ans = min(ans, a);
        }
        if (ans < INF) cout << ans << "\n";
        else cout << -1 << "\n";
    }
}