#pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include using namespace std; template class y_combinator { F f; public: y_combinator(F&& f) : f(std::forward(f)) {} template auto operator()(Args&&... args) const { return f(*this, std::forward(args)...); } }; using ll = long long; using ld = long double; using u8 = uint8_t; using u32 = uint32_t; using u64 = uint64_t; using vi = vector; using vl = vector; using pii = pair; using pll = pair; template > using prique = std::priority_queue, U>; inline constexpr int popcnt(u64 x) noexcept { return __builtin_popcountll(x); } template T floor(T a, T b) noexcept { return a / b - (a % b && (a ^ b) < 0); } template T ceil(T a, T b) noexcept { return floor(a + b - 1, b); } template bool chmin(T& x, const T& y) noexcept { return (x > y ? x = y, true : false); } template bool chmax(T& x, const T& y) noexcept { return (x < y ? x = y, true : false); } void SCAN() {} template void SCAN(H& h, T&... t) { std::cin >> h, SCAN(t...); } #define INT(...) \ int __VA_ARGS__; \ SCAN(__VA_ARGS__) #define LL(...) \ long long __VA_ARGS__; \ SCAN(__VA_ARGS__) #define LD(...) \ long double __VA_ARGS__; \ SCAN(__VA_ARGS__) #define STR(...) \ std::string __VA_ARGS__; \ SCAN(__VA_ARGS__) #define CHAR(...) \ char __VA_ARGS__; \ SCAN(__VA_ARGS__) #define VEC(type, name, size) \ std::vector name(size); \ for (int i = 0; i < (int)size; i++) SCAN(name[i]); #define VV(type, name, h, w) \ std::vector> name(h, std::vector(w)); \ for (int i = 0; i < (int)h; i++) \ for (int j = 0; j < (int)w; j++) SCAN(name[i][j]); #define overload4(a, b, c, d, e, ...) e #define rep1(a) for (long long _i = 0; _i < (a); _i++) #define rep2(i, a) for (long long i = 0; i < (a); i++) #define rep3(i, a, b) for (long long i = (a); i < (b); i++) #define rep4(i, a, b, c) for (long long i = (a); i < (b); i += (c)) #define rep(...) overload4(__VA_ARGS__, rep4, rep3, rep2, rep1)(__VA_ARGS__) #define rrep(i, a, b, c) for (long long i = (a); i > (b); i += (c)) #define all(x) std::begin(x), std::end(x) #define rall(x) std::rbegin(x), std::rend(x) #define len(x) (long long)(size(x)) #define pb push_back #ifndef LOCAL #define debug(...) #endif int precalc[3 << 17][10][3]; inline int inv(int a, int b, int c) { return (a > b) + (a > c) + (b > c); } void run_case() { INT(N, Q); STR(S); vector> idx(10); memset(precalc, -1, sizeof(precalc)); rep(i, N) { rep(j, 10) rep(k, 3) precalc[i + 1][j][k] = precalc[i][j][k]; int d = S[i] - '0'; idx[d].pb(i); rep(k, min(3, len(idx[d]))) { precalc[i + 1][d][k] = idx[d][len(idx[d]) - k - 1]; } } vi cand; rep(x, 0, 1000, 8) if (x >= 100 && to_string(x).find('0') == string::npos) cand.push_back(x); auto f = [&](int l, int r, int tar) -> int { vi vis(10); vi ids; while (tar) { int d = tar % 10; tar /= 10; int idx = precalc[r][d][vis[d]]; if (idx < l) return 1e9; ids.push_back(idx); vis[d]++; } reverse(all(ids)); int ans = 3 * r - 6; assert(len(ids) == 3); ans -= ids[0] + ids[1] + ids[2]; ans += inv(ids[0], ids[1], ids[2]); return ans; }; rep(Q) { INT(l, r); l--; if (r - l == 1) { cout << (S[l] == '8' ? 0 : -1) << "\n"; } else if (r - l == 2) { int d1 = S[l] - '0', d2 = S[l + 1] - '0'; int s = d1 * 10 + d2; int t = d2 * 10 + d1; if (s % 8 == 0) cout << 0 << "\n"; else if (t % 8 == 0) cout << 1 << "\n"; else cout << -1 << "\n"; } else { int ans = 1e9; for (int x : cand) { chmin(ans, f(l, r, x)); } cout << (ans == 1e9 ? -1 : ans) << "\n"; } } } int main() { std::ios_base::sync_with_stdio(false); std::cin.tie(nullptr); std::fixed(std::cout).precision(16); int T = 1; while (T--) run_case(); return 0; }