Cod sursa(job #2765264)

Utilizator Teodor_AxinteAxinte Teodor-Ionut Teodor_Axinte Data 26 iulie 2021 01:02:34
Problema Range minimum query Scor 70
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.35 kb
#include <fstream>
#include <iostream>
#include <vector>


using namespace std;

FILE *fin = fopen("rmq.in","r");
FILE *fout= fopen("rmq.out","w");

const int oo=INT32_MAX;
const int N=100005;

int n,m,o,a,b;
int input[N];
vector<int>segTree(4*N+10,oo);


void constructTree(int input[],vector<int> &segTree,int low,int high,int pos)
{
    if(low==high)
    {
        segTree[pos]=input[low];
        return;
    }
    int mid=(low+high)/2;
    constructTree(input,segTree,low,mid,2*pos+1);
    constructTree(input,segTree,mid+1,high,2*pos+2);

    segTree[pos]=min(segTree[2*pos+1],segTree[2*pos+2]);
}

int rangeMinQuery(vector<int> &segTree, int Qlow, int Qhigh,int low,int high,int pos)
{
    if(Qlow<=low && Qhigh>=high) //total overlap
        return segTree[pos];

    if(Qlow>high || Qhigh<low) //no overlap
        return oo;

    //double overlap

    int mid = (low+high)/2;
    int fiu_st= rangeMinQuery(segTree,Qlow,Qhigh,low,mid,2*pos+1);
    int fiu_dr= rangeMinQuery(segTree,Qlow,Qhigh,mid+1,high,2*pos+2);
    return min(fiu_st,fiu_dr);
}

int main()
{
    fscanf(fin,"%d %d",&n,&m);
    for(int i=0;i<n;i++)
        fscanf(fin,"%d",&input[i]);
    constructTree(input,segTree,0,n-1,0);

    for(;m!=0;m--)
    {
        fscanf(fin,"%d %d",&a,&b);
        int rez=rangeMinQuery(segTree,a-1,b-1,0,n-1,0);
        fprintf(fout,"%d\n",rez);
    }
    return 0;
}