Cod sursa(job #2831094)

Utilizator OrzaSERBANSerban Orza OrzaSERBAN Data 10 ianuarie 2022 20:34:19
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.88 kb
#include <bits/stdc++.h>

using namespace std;
class InParser {
private:
	FILE *fin;
	char *buff;
	int sp;

	char read_ch() {
		++sp;
		if (sp == 4096) {
			sp = 0;
			fread(buff, 1, 4096, fin);
		}
		return buff[sp];
	}

public:
	InParser(const char* nume) {
		fin = fopen(nume, "r");
		buff = new char[4096]();
		sp = 4095;
	}

	InParser& operator >> (int &n) {
		char c;
		while (!isdigit(c = read_ch()) && c != '-');
		int sgn = 1;
		if (c == '-') {
			n = 0;
			sgn = -1;
		} else {
			n = c - '0';
		}
		while (isdigit(c = read_ch())) {
			n = 10 * n + c - '0';
		}
		n *= sgn;
		return *this;
	}

	InParser& operator >> (long long &n) {
		char c;
		n = 0;
		while (!isdigit(c = read_ch()) && c != '-');
		long long sgn = 1;
		if (c == '-') {
			n = 0;
			sgn = -1;
		} else {
			n = c - '0';
		}
		while (isdigit(c = read_ch())) {
			n = 10 * n + c - '0';
		}
		n *= sgn;
		return *this;
	}
};
//ifstream f("rmq.in");
ofstream g("rmq.out");

int n,m,nr;
int v[100005];
int minime[100005][19];
void puneMinime()//maxime cu poz
{
    int i,j,a,b;
    for(i=0;i<=n;i++)
        minime[i][0]=i;
    for(j=1;(1<<j)<=n;j++)
        for(i=0;i+(1<<j)<=n;i++)
    {
        a=minime[i][j-1];
        b=minime[i+(1<<(j-1))][j-1];
        if(v[a]<=v[b])
            minime[i][j]=a;
        else
            minime[i][j]=b;
    }
}
int getMinime(int x,int y)
{
    if(x>y)
        swap(x,y);
    int k,a,b;
    k=log2(y-x+1);
    a=minime[x][k];
    b=minime[y-(1<<k)+1][k];
    if(v[a]<=v[b])
        return a;
    return b;
}
int main()
{
    //ios_base::sync_with_stdio(0);
    //f.tie(0);
    //g.tie(0);
    InParser f("rmq.in");
    int i,x,y;
    f>>n>>m;
    for(i=1;i<=n;i++)
        f>>v[i];
    puneMinime();
    for(i=1;i<=m;i++)
    {
        f>>x>>y;
        g<<v[getMinime(x,y)]<<'\n';
    }
    return 0;
}