Cod sursa(job #1164672)

Utilizator CosminRusuCosmin Rusu CosminRusu Data 2 aprilie 2014 11:26:03
Problema Arbori indexati binar Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 2.54 kb
#include <fstream>
#include <iostream>
#include <vector>
#include <bitset>
#include <string.h>
#include <algorithm>
#include <iomanip>
#include <math.h>
#include <time.h>
#include <stdlib.h>
#include <set>
#include <map>
#include <string>
#include <queue>
#include <deque>

using namespace std;

const char infile[] = "aib.in";
const char outfile[] = "aib.out";

ifstream fin(infile);
ofstream fout(outfile);

const int MAXN = 100005;
const int oo = 0x3f3f3f3f;

typedef vector<int> Graph[MAXN];
typedef vector<int> :: iterator It;

const inline int min(const int &a, const int &b) { if( a > b ) return b;   return a; }
const inline int max(const int &a, const int &b) { if( a < b ) return b;   return a; }
const inline void Get_min(int &a, const int b)    { if( a > b ) a = b; }
const inline void Get_max(int &a, const int b)    { if( a < b ) a = b; }

const int lim = (1<<20);
char buff[lim];
int pos;

inline void get(int &x) {
    x = 0;
    while(!('0' <= buff[pos] && buff[pos] <= '9'))
        if(++ pos == lim) {
            pos = 0;
            fread(buff, 1, lim, stdin);
        }
    while('0' <= buff[pos] && buff[pos] <= '9') {
        x = x * 10 + buff[pos] - '0';
        if(++ pos == lim) {
            pos = 0;
            fread(buff, 1, lim, stdin);
        }
    }
}


int N, M, A[MAXN], aib[MAXN];

inline int lsb(int x) {
    return x & (-x);
}

inline void Update(int pos, int value) {
    for(int i = pos ; i <= N ; i += lsb(i))
        aib[i] += value;
}

inline int Query(int pos) {
    int sum = 0;
    for(int i = pos ; i ; i -= lsb(i))
        sum += aib[i];
    return sum;
}

inline int binarySearch(int value) {
    int li = 1, ls = N, ans = -1;
    while(li <= ls) {
        int mid = ((li + ls) >> 1);
        int val = Query(mid);
        if(val >= value) {
            ls = mid - 1;
            if(val == value)
                ans = mid;
        }
        else li = mid + 1;
    }
    return ans;
}

int main() {
    freopen(infile, "r", stdin);
    get(N);
    get(M);
    for(int i = 1;  i <= N ; ++ i) {
        get(A[i]);
        Update(i, A[i]);
    }
    for(int i = 1 ; i <= M ; ++ i) {
        int op, a, b;
        get(op);
        switch(op) {
            case 0:
                get(a); get(b);
                Update(a, b);
                break;
            case 1:
                get(a); get(b);
                fout << Query(b) - Query(a - 1) << '\n';
                break;
            case 2:
                get(a);
                fout << binarySearch(a) << '\n';
                break;

        }
    }
    fout.close();
    return 0;
}