exercism/dart/difference-of-squares/lib/difference_of_squares.dart

import 'dart:math' show pow;

class DifferenceOfSquares {
  int squareOfSum(int v) {
    int total = 0;
    for(int i = 1; i <= v; i++) {
      total += i;
    }
    return pow(total, 2) as int;
  }

  int sumOfSquares(int v) { 
    int total = 0;
    for(int i = 1; i <= v; i++) {
      total += pow(i, 2) as int;
    }
    return total;
  }

  int differenceOfSquares(int v) => squareOfSum(v) - sumOfSquares(v);
}