Input:   (the individual after crossover and mutation)
Output:   (the fill factor is )
1: Find the position of the elements turned on:
2: Calculate the number of 1 in :
3: Calculate the number of positions in which the value should be reversed:
4: Generate a random position distribution according to :
5: if    then
6:  Set the excess number as 0:
7: else if    then
8: Set the excess number as 1:
9: end if

Algorithm 2: Constrain the fill fact procedure.