A Novel Discrete Global-Best Harmony Search Algorithm for Solving 0-1 Knapsack Problems

Algorithm 2

The procedure of improvising a new harmony of GHS.

(1) for   𝑗=1 to 𝐷  do

(2)  // memory consideration

(3)  if   rand(0,1)⩽HMCR  then

(4)   Choose a harmony 𝑥_𝑖 from HM randomly, 𝑖∈[1..HMS]

(5)    𝑥^′_𝑗=𝑥_𝑖,𝑗

    // pitch adjustment

(6)   if   rand(0,1)⩽PAR(𝑡)  then

(7)    Generate a random integer number 𝑘∈[1..𝐷]

     // 𝑏𝑒𝑠𝑡 represents the index of the best harmony in the HM

(8)     𝑥^′_𝑗=𝑥_best,𝑘

(9)   end if

(10)  else

(11)  𝑥^′_𝑗=𝐿_𝑗+rand(0,1)⋅(𝑈_𝑗−𝐿_𝑗) // random selection

(12)  end if

(13) end for