Cod sursa(job #2590555)

Utilizator stefanpiturStefan Alexandru Pitur stefanpitur Data 28 martie 2020 13:23:56
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.34 kb
#include <iostream>
#include <cstdio>
using namespace std;
const int NMAX = 100002;
int aib[NMAX],aibSize;
void add(int poz, int val){
    do{
        aib[poz] += val;
        poz += poz & (-poz);
    }while(poz <= aibSize);
}
int sum(int poz){
    int result = 0;
    while(poz){
        result += aib[poz];
        poz -= poz & (-poz);
    }
    return result;
}
int search(int val){
    if(aib[1] > val)
        return -1;
    int r = 0, pas = 1 << 16;
    while(pas != 0){
        if(r + pas <= aibSize && aib[r + pas] <= val){
            r += pas;
            val -= aib[r];
        }
        pas /= 2;
    }
    if(val > 0)
        return -1;
    return r;
}
int main()
{
    FILE *fin, *fout;
    int n,m,i,op,a,b,ans;
    fin = fopen("aib.in","r");
    fout = fopen("aib.out","w");
    fscanf(fin,"%d %d",&n,&m);
    aibSize = n;
    for(i=1;i<=n;i++){
        fscanf(fin,"%d",&a);
        add(i,a);
    }
    for(i=1;i<=m;i++){
        fscanf(fin,"%d %d",&op,&a);
        if(op != 2)
            fscanf(fin,"%d",&b);
        if(op == 0)
            add(a,b);
        else{
            if(op == 1)
                ans = sum(b) - sum(a - 1);
            else
                ans = search(a);
            fprintf(fout,"%d\n",ans);
        }
    }
    fclose(fin);
    fclose(fout);
    return 0;
}