//bkt recursiv
//1 permutari n=3 => 6 combinatii
#include <iostream>
 
using namespace std;
 
int n ,st[100];
 
int bun(int pas)
{
    int i;
    for (i=1;i<pas;i++)
        if (st[pas]==st[i])return 0;
    return 1;
}
 
int sol(int pas)
{
    return pas==n;
}
 
void afisare()
{
    int i;
    for(i=1;i<=n;i++)
        cout<< st[i];
    cout << endl;
}
 
void BKT(int pas)
{
    int i;
    for (i=1;i<=n;i++)
    {
        st[pas]=i;
        if (bun(pas))
            if (sol(pas))afisare();
        else BKT(pas+1);
    }
}
 
int main()
{
    n=5;
    BKT(1);
    return 0;
}
 

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