Finding out all possibilities using Javascript-CodePudding

Suppose I have a JavaScript array as follows:

var arr = [1,2,3,4,5,6,7,8,9]

I want to get all the possible sets using three numbers from the above array. For example

var possibilities = [[1,1,1], ..., [1,2,3], [1,2,4], ......, [4,2,1], [4,2,2], [9,9,9]]

I hope I am able to explain this question to you.

CodePudding user response：

Try this, but please, make sure this is what you want, because generate 729 items in result array

var arr = [1,2,3,4,5,6,7,8,9]

let result = [];

for(let i = 0; i < arr.length; i  ) {
  for (let j = 0; j < arr.length; j  ) {
    for (let k = 0; k < arr.length; k  ) {
      result.push([arr[i], arr[j], arr[k]]) 
    }
  }
}

console.log(result)

CodePudding user response：

Time and Space complexities are n^3. It is the minimum we can do, by the way.

var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9];

let possibilities = [];

arr.forEach(first => {
    arr.forEach(second => {
        arr.forEach(third => {
            possibilities.push([first, second, third]);
        })
    })
})

console.log(possibilities);