Cod sursa(job #2999544)

Utilizator iProgramInCppiProgramInCpp iProgramInCpp Data 11 martie 2023 10:20:07
Problema Arbori indexati binar Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.2 kb
#include <cstdio>
using namespace std;

int aib[100001], n;

int thing(int x)
{
    /// example
    /// x  = b101100100
    /// x-1= b101100011 = y
    /// x^y= b000000111 = z
    /// z&x= b000000100

    return (x ^ (x - 1)) & x;
}

void Add(int pos, int val)
{
    for (int i = pos; i <= n; i += thing(i))
        aib[i] += val;
}

int Query(int pos)
{
    int x = 0;
    for (int i = pos; i > 0; i -= thing(i))
        x += aib[i];
    return x;
}

int Query2(int a)
{
    for (int i=1; i<=n; i++)
    {
        int q = Query(i);
        if (q == a) return i;
        if (q > a) return -1;
    }
    return -1;
}

int main()
{
    ios_base.sync_with_stdio(false);
    freopen("aib.in",  "r", stdin);
    freopen("aib.out", "w", stdout);

    int m;
    scanf("%d%d", &n, &m);
    for (int i=1; i<=n; i++)
    {
        int a;
        scanf("%d",&a);
        Add(i, a);
    }

    for (int i=1; i<=m; i++)
    {
        int x,a,b=0;
        scanf("%d%d",&x,&a);
        if (x != 2) scanf("%d",&b);

        if(x==0) Add(a,b);
        if(x==1) printf("%d\n", Query(b) - Query(a - 1));
        if(x==2) printf("%d\n", Query2(a));
    }


    return 0;
}