Cod sursa(job #71364)

Utilizator DastasIonescu Vlad Dastas Data 10 iulie 2007 13:17:02
Problema Semne Scor 5
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.34 kb
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define maxn 50000
#define fout out

FILE *in = fopen("semne.in","r"), *out = fopen("semne.out","w");

int a[maxn];
char semn[maxn];
int schimb[maxn] = {0};
int n;
long long s;

void read()
{
    fscanf(in, "%d %lld", &n, &s);

    for ( int i = 0; i < n; ++i )
        fscanf(in, "%d", &a[i]), schimb[i] = 0;
}

long long sum()
{
    long long sm = 0;

    for ( int i = 0; i < n; ++i )
        if ( semn[i] == 0 )
            sm -= a[i];
        else
            sm += a[i];

    return sm;
}

int main()
{
    read();
    srand((unsigned)time(0));

    long long sol = 0;

    while ( sol != s )
    {
        int q = rand();
        int p = rand();
        int t = (p + q) % n;

        semn[t] ^= 1;

        //sol = sum();

        if ( schimb[t] == 0 )
        {
            if ( semn[t] == 0 )
                sol -= a[t];
            else
                sol += a[t];

            schimb[t] = 1;
        }
        else
        {
            if ( semn[t] == 0 )
                sol = sol - 2*a[t];
            else
                sol = sol + 2*a[t];
        }
    }

    for ( int i = 0; i < n; ++i )
        if ( semn[i] == 0 )
            fprintf(fout, "-");
        else
            fprintf(fout, "+");



	return 0;
}