CODE EXAMPLE FOR PYTHON

Python find permutations of operators between each digit in a given string of digits will result in a particular answer

from itertools import permutations,combinations_with_replacement
numbers   = ["9","8","1","2"]
target    = 24
operators = ["+","-","*","/"]
groups    = ['X+X+X+X', 'X+X+(X+X)', 'X+(X+X)+X', '(X+X+X)+X', '(X+X)+X+X', 'X+(X+X+X)', '((X+X)+X)+X', 'X+(X+(X+X))', 'X+((X+X)+X)', '(X+X)+(X+X)', '(X+(X+X))+X']
seen      = set()
for values in permutations(numbers,len(numbers)):
    for operCombo in combinations_with_replacement(operators,len(numbers)-1):
        for oper in permutations(operCombo,len(numbers)-1):
            formulaKey = "".join(oper+values)
            if formulaKey in seen: continue # ignore variations on parentheses alone
            for pattern in groups:
                formula = "".join(o+p for o,p in zip([""]+list(oper), pattern.split("+")))
                formula = "".join(v+p for v,p in zip([""]+list(values),formula.split("X")))
                try:
                    if eval(formula) == target:
                        print(formula,"=",target)
                        seen.add(formulaKey)
                        break 
                except: pass