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| #include <bits/stdc++.h> using namespace std;
typedef long long ll; const int MOD = 1000000007; const int MAXN = 200010;
ll powmod(ll a, ll b, ll mod) { ll res = 1; a %= mod; for (; b; b >>= 1) { if (b & 1) res = res * a % mod; a = a * a % mod; } return res; }
class Fenwick { public: vector<ll> tree; int n; Fenwick(int _n) : n(_n), tree(_n + 2, 0) {} void update(int idx, ll val) { idx++; while (idx <= n + 1) { tree[idx] = (tree[idx] + val) % MOD; idx += idx & -idx; } } ll query(int idx) { idx++; ll sum = 0; while (idx > 0) { sum = (sum + tree[idx]) % MOD; idx -= idx & -idx; } return sum; } ll query(int l, int r) { if (l > r) return 0; return (query(r) - query(l - 1) + MOD) % MOD; } };
class SegMax { public: vector<int> tree; int n; SegMax(int _n) : n(_n), tree(4 * _n + 10, 0) {} void build(int node, int start, int end, const vector<int>& a) { if (start == end) { tree[node] = a[start]; return; } int mid = (start + end) / 2; build(2 * node, start, mid, a); build(2 * node + 1, mid + 1, end, a); tree[node] = max(tree[2 * node], tree[2 * node + 1]); } int query(int node, int start, int end, int l, int r) { if (r < start || end < l) return -1; if (l <= start && end <= r) return tree[node]; int mid = (start + end) / 2; int p1 = query(2 * node, start, mid, l, r); int p2 = query(2 * node + 1, mid + 1, end, l, r); if (p1 == -1) return p2; if (p2 == -1) return p1; return max(p1, p2); } };
int main() { ios::sync_with_stdio(false); cin.tie(0); int t; cin >> t; for (int cas = 0; cas < t; ++cas) { int n, m; cin >> n >> m; vector<int> a(n + 1); for (int i = 1; i <= n; ++i) cin >> a[i]; SegMax sm(n); sm.build(1, 1, n, a); vector<int> M(n + 1, -1); int maxl = 0; bool iszero = false; for (int i = 0; i < m; ++i) { int l, r; cin >> l >> r; M[r] = max(M[r], l); maxl = max(maxl, l); if (sm.query(1, 1, n, l, r) == 0) iszero = true; } if (iszero) { cout << 0 << '\n'; continue; } vector<int> last_forced(n + 1, 0); for (int i = 1; i <= n; ++i) { if (a[i] == 10) last_forced[i] = i; else last_forced[i] = last_forced[i - 1]; } vector<ll> Q(n + 1, 1); Q[0] = 1; for (int i = 1; i <= n; ++i) { if (a[i] == 10) Q[i] = 1; else Q[i] = Q[i - 1] * (10LL - a[i]) % MOD; } vector<ll> DP(n + 1, 0); DP[0] = 1; Fenwick ft(n); ll val = DP[0] * powmod(Q[0], MOD - 2, MOD) % MOD; ft.update(0, val); ll run = -1; for (int i = 1; i <= n; ++i) { run = max(run, (ll)M[i - 1]); int mj_seg = max(0LL, run); int mj = max(mj_seg, last_forced[i - 1]); ll qsum = ft.query(mj, i - 1); ll temp = qsum * Q[i - 1] % MOD; DP[i] = (ll)a[i] * temp % MOD; val = DP[i] * powmod(Q[i], MOD - 2, MOD) % MOD; ft.update(i, val); } vector<ll> S(n + 2, 1); for (int i = n; i >= 1; --i) { S[i] = S[i + 1] * (10LL - a[i]) % MOD; } ll numer = 0; for (int i = 0; i <= n; ++i) { if (i >= maxl) { numer = (numer + DP[i] * S[i + 1] % MOD) % MOD; } } ll inv10 = powmod(10LL, MOD - 2, MOD); ll inv10n = powmod(inv10, n, MOD); ll ans = numer * inv10n % MOD; cout << ans << '\n'; } return 0; }
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