Cod sursa(job #3350233)

Utilizator eric_dragosDragos Eric eric_dragos Data 6 aprilie 2026 15:46:01
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.21 kb
#include <bits/stdc++.h>
#define ll long long
using namespace std;
ifstream fin("rmq.in");
ofstream fout("rmq.out");
vector<int> a, st;
void build(int node, int l, int r){
    if(l == r){
        st[node] = a[l];
        return;
    }
    int m = (l+r)/2;
    build(2*node+1, l, m);
    build(2*node+2, m+1, r);

    st[node] = min(st[2*node+1], st[2*node+2]);
}
void update(int node, int l, int r, int i, int v){
    if(l == r){
        st[i] = v;
        return;
    }
    int m = (l+r)/2;
    if(i < m) update(2*node+1, l, m, i, v);
    else update(2*node+2, m+1, r, i, v);

    st[node] = min(st[2*node+1], st[2*node+2]);
}
int query(int n, int l, int r, int lq, int rq){
    if(r < lq || l > rq) return INT_MAX;
    if(lq <= l && r <= rq) return st[n];
    int m = (l+r)/2;
    int min1 = query(2*n+1, l, m, lq, rq);
    int min2 = query(2*n+2, m+1, r, lq, rq);

    return min(min1, min2);
}
int main(){
    int n,m;
    fin >> n >> m;
    a.resize(n+1, 0);
    st.resize(4*n, 0);
    for(int i = 1; i<=n; i++){
        fin >> a[i];
    }
    build(1, 1, n);
    while(m--){
        int a,b;
        fin  >> a >> b;
        fout << query(1, 1, n, a, b) << '\n';
    }

    return 0;
}