Salesforce Opportunity Code

An opportunity code is a positive integer represented as a string.

You are given:

• allowed_digits[]: a sorted array containing the digits that may be used.
• n: a positive integer.

Construct the smallest positive multiple of n such that:

• Every digit belongs to allowed_digits.
• No two consecutive digits are equal.
• The number has no leading zeros.

If no such number exists, return "-1".

Function Signature

string findSmallestOpportunityCode(vector<int> allowed_digits, int n);

Parameters

• allowed_digits: Allowed digits.
• n: Required divisor.

Returns

Return the smallest valid opportunity code or "-1" if it is impossible.