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 <bits/stdc++.h>
#define all(vec) vec.begin(), vec.end()
using namespace std;
using ll = long long;
using P = pair<int, int>;
constexpr ll INF = (1LL << 30) - 1LL;
constexpr ll LINF = (1LL << 60) - 1LL;
constexpr ll MOD = 1e9 + 7;
template <typename T> void chmin(T &a, T b) { a = min(a, b); }
template <typename T> void chmax(T &a, T b) { a = max(a, b); }
template <typename T> struct Segtree {
    inline T merge(const T &a, const T &b) { return min(a, b); }
    inline void act(T &a, const T &b) { a = b; }
    int n, e;
    vector<T> dat;
    Segtree(int n_, int e) : e(e) {
        n = 1;
        while (n < n_) {
            n <<= 1;
        }
        dat.resize(2 * n, e);
    }
    void set(int k, const T &x) {
        k += n;
        act(dat[k], x);
        k >>= 1;
        while (k > 0) {
            dat[k] = merge(dat[k << 1], dat[k << 1 | 1]);
            k >>= 1;
        }
    }
    T get(const int &a, const int &b, int k, int l, int r) {
        if (b <= l || r <= a) {
            return e;
        }
        if (a <= l && r <= b) {
            return dat[k];
        }
        return merge(get(a, b, k << 1, l, (l + r) >> 1),
                     get(a, b, k << 1 | 1, (l + r) >> 1, r));
    }
    inline T get(const int &a, const int &b) { //[a,b)
        if (a >= b) {
            return e;
        }
        return get(a, b, 1, 0, n);
    }
    int find(const int &a, const int &b, const T &x, int k, int l, int r) {
        if (b <= l || r <= a || dat[k] > x) {
            return -1;
        }
        if (k >= n) {
            return k - n;
        }
        int il = find(a, b, x, k << 1, l, (l + r) >> 1);
        if (il != -1) {
            return il;
        }
        return find(a, b, x, k << 1 | 1, (l + r) >> 1, r);
    }
    inline int find(const int &a, const int &b, const T &x) {
        if (a >= b) {
            return -1;
        }
        return find(a, b, x, 1, 0, n);
    }
};
int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n, q;
    cin >> n >> q;
    Segtree<int> seg(n, (1LL << 31) - 1LL);
    for (int i = 0; i < q; i++) {
        int t, l, r;
        cin >> t >> l >> r;
        if (t == 0) {
            seg.set(l, r);
        } else {
            ++r;
            cout << seg.get(l, r) << "\n";
        }
    }
}