Find the Divisibility Array of a String - Build Modulo [JS]

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Description 

Solution: Build Modulo

Build up the modulo sum on the fly as we process each digit in word.

Time Complexity: O(n)
Space Complexity: O(n)

var divisibilityArray = function(word, m) {
  let n = word.length, div = Array(n).fill(0), sum = 0;
  for (let i = 0; i < n; i++) {
    let digit = Number(word[i]);
    sum = (sum * 10 + digit) % m;
    if (sum === 0) div[i] = 1;
  }
  return div;
};
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