Project Euler – Problem 206 Solution

Problem

Find the unique positive integer whose square has the form 1_2_3_4_5_6_7_8_9_0,

where each “_” is a single digit.

Solution

Initially I started solving this problem by creating all permutations of 19 digits numbers which fits the required pattern and iteratively square rooting them to find a square root which is a whole number. Unfortunately thanks to rounding errors this approach doesn’t give me the correct answer so I resorted to iterating through the square roots and brute forcing it instead.

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