title: Maximum Subsequence Sum Such That No Three Are Consecutive
signature: function maximum_subsequence_sum_such_that_no_three_are_consecutive(arr, n)
source_py: def maximum_subsequence_sum_such_that_no_three_are_consecutive(arr, n):
      sum = [0 for k in range(n)]
      if (n >= 1):
          sum[0] = arr[0]
      if (n >= 2):
          sum[1] = (arr[0] + arr[1])
      if (n > 2):
          sum[2] = max(sum[1], max((arr[1] + arr[2]), (arr[0] + arr[2])))
      for i in range(3, n):
          sum[i] = max(max(sum[(i - 1)], (sum[(i - 2)] + arr[i])), ((arr[i] + arr[(i - 1)]) + sum[(i - 3)]))
      return sum[(n - 1)]
source_cpp: int maximum_subsequence_sum_such_that_no_three_are_consecutive(vector<int> arr, int n) {
    int sum [ n ];
    if ( n >= 1 ) sum [ 0 ] = arr [ 0 ];
    if ( n >= 2 ) sum [ 1 ] = arr [ 0 ] + arr [ 1 ];
    if ( n > 2 ) sum [ 2 ] = max ( sum [ 1 ], max ( arr [ 1 ] + arr [ 2 ], arr [ 0 ] + arr [ 2 ] ) );
    for ( int i = 3;
    i < n;
    i ++ ) sum [ i ] = max ( max ( sum [ i - 1 ], sum [ i - 2 ] + arr [ i ] ), arr [ i ] + arr [ i - 1 ] + sum [ i - 3 ] );
    return sum [ n - 1 ];
  }