Cod sursa(job #657553)

Utilizator repp4raduRadu-Andrei Szasz repp4radu Data 6 ianuarie 2012 18:59:51
Problema Semne Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.8 kb
#include <cstdio>
#include <vector>
#include <cstdlib>
#include <ctime>

#define MAX 50001

using namespace std;

vector<int> plus, minus;
int semn[MAX];
//semn = 1 pt plus
//semn = 0 pt minus
long long suma;
long long sumaPartiala;

int n;
int v[MAX];

void citire()
{
    freopen("semne.in", "r", stdin);
    scanf("%d %lld", &n, &suma);
    for(int i = 1; i <= n; i++)
    {
        scanf("%d", &v[i]);
    }
    fclose(stdin);
}

void firstAssignment()
{
    for(int i = 1; i <= n; i++)
    {
        if(sumaPartiala + v[i] > suma)
        {
            sumaPartiala -= v[i];
            semn[i] = 0;
            minus.push_back(i);
        }
        else
        {
            sumaPartiala += v[i];
            semn[i] = 1;
            plus.push_back(i);
        }
    }
}

void afisare()
{
    freopen("semne.out", "w", stdout);
    for(int i = 1; i <= n; i++)
    {
        if(semn[i])
        {
            printf("+");
        }
        else
            printf("-");
    }
    fclose(stdout);
}

int main()
{
    srand(time(NULL));
    citire();
    firstAssignment();
    while(suma != sumaPartiala)
    {
        if(sumaPartiala > suma)
        {
            int which = rand() % plus.size();
            sumaPartiala -= (2 * v[plus[which]]);
            minus.push_back(plus[which]);
            semn[plus[which]] = 0;
            plus[which] = plus[plus.size() - 1];
            plus.pop_back();
        }
        else
        {
            int which = rand() % minus.size();
            sumaPartiala += (2 * v[minus[which]]);
            plus.push_back(minus[which]);
            semn[minus[which]] = 1;
            minus[which] = minus[minus.size() - 1];
            minus.pop_back();
        }
    }
    afisare();
    return 0;
}