线段树

#include <bits/stdc++.h>
using namespace std;

const int N = 1e5 + 5;
int a[N];
int seg[N * 4];

void build(int id, int l, int r){
    if(l == r){
        seg[id] = a[l];
        return;
    }
    int mid = (l + r) >> 1;
    build(id<<1, l, mid);
    build(id<<1|1, mid+1, r);
    seg[id] = min(seg[id<<1], seg[id<<1|1]);
}

int query(int id, int l, int r, int ql, int qr){
    if(ql <= l && r <= qr) return seg[id];
    int mid = (l + r) >> 1;
    int ans = INT_MAX;

    if(ql <= mid) ans = min(ans, query(id<<1, l, mid, ql, qr));
    if(qr > mid)  ans = min(ans, query(id<<1|1, mid+1, r, ql, qr));

    return ans;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, Q;
    cin >> n >> Q;

    for(int i = 0; i < n; i++)
        cin >> a[i];

    build(1, 0, n-1);

    while(Q--){
        int l, r;
        cin >> l >> r;
        cout << query(1, 0, n-1, l, r) << "\n";
    }
}