Cod sursa(job #2022266)

Utilizator MaligMamaliga cu smantana Malig Data 16 septembrie 2017 10:19:47
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <bits/stdc++.h>

using namespace std;
ifstream in("rmq.in");
ofstream out("rmq.out");

#define ll long long
#define ull unsigned long long
#define ui unsigned int
#define pb push_back
#define mp make_pair
const int NMax = 1e5 + 5;
const int inf = 1e9 + 5;
using zint = int;

int N,M;
int v[NMax],rmq[NMax][20],lg[NMax];

int main() {
    in>>N>>M;
    for (int i=1;i <= N;++i) {
        in>>v[i];
        rmq[i][0] = v[i];
    }

    lg[1] = 0;
    for (int i=2;i <= N;++i) {
        lg[i] = lg[i/2] + 1;
    }

    for (int p=1;(1<<p) <= N;++p) {
        for (int i=1;i + (1<<p) <= N;++i) {
            int val1 = rmq[i][p-1],
                val2 = rmq[i + (1<<(p-1))][p-1];
            rmq[i][p] = min(val1,val2);
        }
    }

    while (M--) {
        int a,b;
        in>>a>>b;

        int p = lg[b-a+1],
            val1 = rmq[a][p],
            val2 = rmq[b - (1<<p) + 1][p];

        out<<min(val1,val2)<<'\n';
    }

    in.close();out.close();
    return 0;
}