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template<typename T>
struct RMQ {
  const T INF = numeric_limits<T>::max();
  int n;
  vector<T> dat;

  RMQ(int m) {
    int x = 1;
    while (m > x) x *= 2;
    n = x;
    dat.resize(2*x-1, INF);
  }

  void update(int i, T x) {
    i += n-1;
    dat[i] = x;
    while (i > 0) {
      i = (i - 1) / 2;
      dat[i] = min(dat[i*2+1], dat[i*2+2]);
    }
  }

  T query(int a, int b) { return query_sub(a, b, 0, 0, n); }
  T query_sub(int a, int b, int k, int l, int r) {
    if (r <= a || b <= l) return INF;
    else if (a <= l && r <= b) return dat[k];
    else {
      T vl = query_sub(a, b, k*2+1, l, (l+r)/2);
      T vr = query_sub(a, b, k*2+2, (l+r)/2, r);
      return min(vl, vr);
    }
  }
};