Cod sursa(job #1948898)

Utilizator ciprianprohozescuProhozescu Ciprian ciprianprohozescu Data 1 aprilie 2017 16:00:44
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.49 kb
#include <fstream>
#define NMAX 100010

using namespace std;

FILE *fin, *fout;

int n, m, ain[4 * NMAX];

void update(int x, int q, int st, int dr, int nod);
int calcul(int a, int b, int st, int dr, int nod);

int main()
{
    int i, x, tip, a, b;
    fin = fopen("arbint.in", "r");
    fout = fopen("arbint.out", "w");
    fscanf(fin, "%d%d", &n, &m);
    for (i = 1; i <= n; i++)
    {
        fscanf(fin, "%d", &x);
        update(i, x, 1, n, 1);
    }
    for (i = 1; i <= m; i++)
    {
        fscanf(fin, "%d%d%d", &tip, &a, &b);
        if (!tip)
            fprintf(fout, "%d\n", calcul(a, b, 1, n, 1));
        else
            update(a, b, 1, n, 1);
    }
    fclose(fout);
    return 0;
}

void update(int x, int q, int st, int dr, int nod)
{
    int mij = (st + dr) / 2;
    if (st > dr)
        return ;
    if (st == dr && st == x)
        ain[nod] = q;
    else if (x <= mij)
    {
        update(x, q, st, mij, 2 * nod);
        ain[nod] = max(ain[2 * nod], ain[2 * nod + 1]);
    }
    else if (x > mij)
    {
        update(x, q, mij + 1, dr, 2 * nod + 1);
        ain[nod] = max(ain[2 * nod], ain[2 * nod + 1]);
    }
    return ;
}
int calcul(int a, int b, int st, int dr, int nod)
{
    int x = 0, y = 0, mij = (st + dr) / 2;
    if (st >= a && dr <= b)
        return ain[nod];
    if (a <= mij)
        x = calcul(a, b, st, mij, 2 * nod);
    if (b > mij)
        y = calcul(a, b, mij + 1, dr, 2 * nod + 1);
    return max(x, y);
}