Cod sursa(job #2874714)

Utilizator AlexNeaguAlexandru AlexNeagu Data 20 martie 2022 00:10:08
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.89 kb
#include <bits/stdc++.h>
using namespace std;
ifstream in("rmq.in");
ofstream out("rmq.out");
const int nmax = 100006;
const int LOG = 21;
int dpMin[nmax][LOG], N, M, logaritm[nmax];
void computeRMQ() {
    for(int i = 1; i < LOG; ++i) {
        for(int j = 1; j + (1 << i) - 1 <= N; ++j) {
            int pLen = 1 << (i - 1);
            dpMin[j][i] = min(dpMin[j][i - 1], dpMin[j + pLen][i - 1]);
        }
    }
}
int get(int L, int R) {
    int len = R - L + 1;
    int log = logaritm[len];
    return min(dpMin[L][log], dpMin[R - (1 << log) + 1][log]);
}

int main()  {
    logaritm[1] = 0;
    for(int i = 2; i < nmax; ++i) {
        logaritm[i] = logaritm[i / 2] + 1;
    }
    in >> N >> M;
    for(int i = 1; i <= N; ++i) {
        int x;
        in >> x;
        dpMin[i][0] = x;
    }
    computeRMQ();
    for(int i = 0; i < M; ++i) {
		int L, R;
		in >> L >> R;
		out << get(L, R) << '\n';
	}
}