Problem:
Range Minimum Query (RMQ)

Write a program which manipulates a sequence A = {a0, a1, . . . , an-1} with the following operations:

find(s, t): report the minimum element in as, as+1, . . . ,at.

update(i, x): change ai to x.

Note that the initial values of ai (i = 0, 1, . . . , n−1) are 231-1.

Input

n q
com0 x0 y0
com1 x1 y1
...
comq−1 xq−1 yq−1

In the first line, n (the number of elements in A) and q (the number of queries) are given. Then, q queries are given where com represents the type of queries. '0' denotes update(xi, yi) and '1' denotes find(xi, yi).

Output

For each find operation, print the minimum element.

Constraints

1 ≤ n ≤ 100000

1 ≤ q ≤ 100000

If comi is 0, then 0 ≤ xi < n, 0 ≤ yi < 231-1.

If comi is 1, then 0 ≤ xi < n, 0 ≤ yi < n.

Sample Input 1

3 5
0 0 1
0 1 2
0 2 3
1 0 2
1 1 2

Sample Output 1

1
2

Sample Input 2

1 3
1 0 0
0 0 5
1 0 0

Sample Output 2

2147483647
5

Solution in C++14 (judge verdict: Accepted)

#include<iostream>
#include<vector>

using std::cin;
using std::cout;
using std::endl;

template<class T,class F>
struct segment_tree{
  std::vector<T> data;
  int n;
  F f;
  T identity;
  segment_tree(){}
  segment_tree(int sz,T ide,F _f):f(_f),identity(ide){
    n = 1;
    while(n<sz)n<<=1;
    data.resize(2*n,identity);
  }
  void set(int i,T x){
    i += n;
    data[i] = x;
    while(i){
      i>>=1;
      data[i] = f(data[i<<1|0],data[i<<1|1]);
    }
  }
  T query(int l,int r)const{
    l += n, r += n;
    T x = identity;
    while(l<r){
      if(l&1)x = f(x,data[l++]);
      if(r&1)x = f(x,data[--r]);
      l>>=1, r>>=1;
    }
    return x;
  }
  T operator[](int i)const{
    return data[i+n];
  }
};
template<class T,class F>
auto make_segtree(int n,T ide,F f){
  return segment_tree<T,F>(n,ide,f);
}

signed main(){
  int n;
  cin>>n;
  auto rmq = make_segtree<int64_t>(n,(1LL<<31)-1,[](int a,int b){return a<=b?a:b;});
  int q;
  cin>>q;
  while(q--){
    int com,x,y;
    cin>>com>>x>>y;
    if(com==0){
      rmq.set(x,y);
    }else{
      cout<< rmq.query(x,y+1) <<endl;
    }
  }
}