Loop back to the beginning of the code if IF condition didn't satisfy-CodePudding

I am trying to find a random sample of 3 numbers from a given array from where its sum results to 0.

Output should be storing all the triplets which satisfy it, like below

output - [-1, 0, 1] , [-1, 2, -1]

import random
nums = [-1,0,1,2,-1,-4]
l = 0
w=[]

def fun():
    k = random.sample(nums, 3)
    for i in k:
        l = l i
    if l == 0:
        print(k)
        w.append(k)
    else:
        fun()

fun()
print(w)

Another way i have tried, but no luck. kindly please modify my code to make it work thank you in advance.

import random
nums = [-1,0,1,2,-1,-4]

k = random.sample(nums, 3)
l = 0
w = []

for i in k:
    l = l i
if l == 0:
    w.append(k)
    #print(w)
else:
    #go back to the top of the program

print(w)

CodePudding user response：

If you are trying to just find any solution, you could do it by guessing as follows:

import random

nums = [-1,0,1,2,-1,-4]
num = 3

def find_by_guessing(nums, num, target=0):
    while True:
        guess = random.sample(nums, num)
        if sum(guess) == target:
            return guess

sol = find_by_guessing(nums, num)
print(sol)

prints

[1, -1, 0]

If you want to find all possible solutions, you probably want to not guess but search all candidates exhausitvely, e.g. as follows:

from itertools import combinations

def find_all(nums, num, target=0):
    solutions = []
    for candidate in combinations(nums, num):
        if sum(candidate) == target:
            solutions.append(list(candidate))
    return solutions

sol = find_all(nums, num)
print(sol)

prints

[[-1, 0, 1], [-1, 2, -1], [0, 1, -1]]