Problem 52: Permuted multiples

It can be seen that the number, 125874, and its double, 251748, contain exactly the same digits, but in a different order.

Find the smallest positive integer, x, such that 2x, 3x, 4x, 5x, and 6x, contain the same digits.

C++ source code

#include <iostream>
#include <set>
#include <cassert>

using namespace std;

class PE0052
{
public:
    set<int> getDigits(int x, int multiple);
    void findSmallestPositiveInteger();
};

set<int> PE0052::getDigits(int x, int multiple)
{
    set<int> digits_s;

    x *= multiple;
    while(x> 0)
    {
        digits_s.insert(x % 10);
        x /= 10; 
    }

    return digits_s;
}

void PE0052::findSmallestPositiveInteger()
{
    for (int n=100000; n<1000000; n++) 
    {
        if ((getDigits(n, 1) == getDigits(n, 2)) && 
            (getDigits(n, 2) == getDigits(n, 3)) &&
            (getDigits(n, 3) == getDigits(n, 4)) &&
            (getDigits(n, 4) == getDigits(n, 5)) &&
            (getDigits(n, 5) == getDigits(n, 6)))
        {
            cout << \"The smallest positive integer \" << n << \", x, \";
            cout << \"2x, 3x, 4x, 5x and 6x, contain the same digits.\" << endl;
            break;
        }
    }
}

int main()
{
    PE0052 pe0052;

    assert(pe0052.getDigits(125874,1)==pe0052.getDigits(125874,2));

    pe0052.findSmallestPositiveInteger();
        
    return 0;
}

Python source code

def getDigitsString(x, multiple):
    return sorted(str(multiple*x))

def findSmallestPositiveInteger():
    for x in range(10**5, 10**6):
        if getDigitsString(x, 1) == getDigitsString(x, 2) and \\
           getDigitsString(x, 2) == getDigitsString(x, 3) and \\
           getDigitsString(x, 3) == getDigitsString(x, 4) and \\
           getDigitsString(x, 4) == getDigitsString(x, 5) and \\
           getDigitsString(x, 5) == getDigitsString(x, 6):
            return x
    return 0

def main():
    assert getDigitsString(125874, 1) == getDigitsString(125874, 2)
    print(\"The smallest integer\",findSmallestPositiveInteger(),\\
		  \", multiples from 1 to 6, contain the same digits.\")

if  __name__ == \'__main__\':
    main()
    
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