How to generate all possible variations with repetitions in C

I'm looking for an algorithm in C to generate all possible variations with repetitions for set length and from n elements. For example, if the length is 3 and the elements are: 1, 2. The output should be :

1 1 1

1 1 0

1 开发者_JS百科0 0

1 0 1

0 0 0

0 0 1

0 1 1

0 1 0

I already looked for the solutions here, but all I could find were implementations in Java or Python and I don't know how to rewrite them to C. Can somebody please post a C code for this problem here?

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void g(int l,int v,char *c)
{
    int i=v;
    if (l--==0) 
        puts(c);
    else 
        while(i)
            g(l,(c[l]='0'+--i,v),c);
}

void f(int l,int v)
{
    char c[l+2];
    g(((c[l]=13,c[l+1]=0),l),v,c);
}

int main()
{
    f(3,2);
    return 0;
}

Tested, works!, updated to fix readability issue

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It's nothing else than generating all the numbers of length N in base B (in your case N is 3 and B is 2).