Cod sursa(job #2841308)

Utilizator mihnea.cazan15mihnea cazan mihnea.cazan15 Data 29 ianuarie 2022 15:27:55
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.86 kb
#include <fstream>

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

int a[100005],m[100005][21];
int log(int n)
{
    for(int i=0;i<30;i++)
    {
        if((1<<i)>n)
           return i-1;
    }
}

int main()
{
    int n,q;
    cin>>n>>q;
    for(int i=0;i<n;i++)
        cin>>a[i];
    for(int i=0;i<n;i++)
        m[i][0]=i;
    for(int j=1;(1<<j)<=n;j++)
    {
        for(int i=0;i+(1<<j)-1<n;i++)
        {
            int x=m[i][j-1];
            int y=m[i+(1<<(j-1))][j-1];
            if(a[x]<=a[y])
               m[i][j]=x;
            else
                m[i][j]=y;
        }
    }
    while(q--)
    {
        int i,j;
        cin>>i>>j;
        i--,j--;
        int k=log(j-i+1);
        int x=m[i][k];
        int y=m[j-(1<<k)+1][k];
        cout<<min(a[x],a[y])<<"\n";
    }
    return 0;
}