Cod sursa(job #779339)

Utilizator visanrVisan Radu visanr Data 17 august 2012 15:21:17
Problema Arbori de intervale Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.56 kb
#include <cstdio>
#include <cstdlib>
#include <algorithm>
using namespace std;

#define leftSon (node << 1)
#define rightSon ((node << 1) + 1)
#define nmax 800010

int AInt[nmax], N, M, T, A, B, X, sol;

void Update(int node, int left, int right, int pos, int value);
void Query(int node, int left, int right, int start, int end);

int main()
{
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);
    int i;
    scanf("%i %i", &N, &M);
    for(i = 1; i <= N; i++)
    {
          scanf("%i", &X);
          Update(1, 1, N, i, X);
    }
    for(; M; M --)
    {
          scanf("%i %i %i", &T, &A, &B);
          if(T) Update(1, 1, N, A, B);
          else
          {
              sol = 0;
              Query(1, 1, N, A, B);
              printf("%i\n", sol);
          }
    }
    return 0;
}

void Update(int node, int left, int right, int pos, int value)
{
     if(left == right)
     {
             AInt[node] = value;
             return ;
     }
     int mid = (left + right) / 2;
     if(pos <= mid) Update(leftSon, left, mid, pos, value);
     else Update(rightSon, mid + 1, right, pos, value);
     AInt[node] = max(AInt[leftSon], AInt[rightSon]);
}

void Query(int node, int left, int right, int start, int end)
{
     if(start <= left && right <= end)
     {
              sol = max(sol, AInt[node]);
              return ;
     }
     int mid = (left + right) / 2;
     if(start <= mid) Query(leftSon, left, mid, start, end);
     if(mid < end) Query(rightSon, mid + 1, right, start, end);
}