How to realize Cartesian product of array

problem background: when you encounter this requirement in development, if the objects in an array are in the following format, can you do Cartesian product operation according to the difference of sidePos to get the following strings of different sidePos fields? The test field does not have any meaning, but only indicates the field name 

item.value = `{"test": {"sidePos": "", "val": 0}, {"sidePos": "", "val": 1}}`
item.value = `{"test": {"sidePos": "", "val": 0}, {"sidePos": "", "val": 4}}`
item.value = `{"test": {"sidePos": "", "val": 2}, {"sidePos": "", "val": 1}}`
item.value = `{"test": {"sidePos": "", "val": 2}, {"sidePos": "", "val": 4}}`
item.value = `{"test": {"sidePos": "", "val": 3}, {"sidePos": "", "val": 1}}`
item.value = `{"test": {"sidePos": "", "val": 3}, {"sidePos": "", "val": 4}}`

beginners ask for advice ~

Javascript
Mar.02,2021
  1. put "hundred" in one array and "ten" in another
  2. the result array of two-layer loops combined into nimm elements

pseudo code: 

for each i in 
    for each j in 
        result.push(i + j)

another way of implementation:

  1. two-layer loop. Determine whether the two elements are the same in the inner loop. If they are not the same, they are combined. If the same is the same, skip
.

pseudo code: 

for each i in arr
    for each j in arr
        if (i.sidePos != j.sidePos)
            result.push(i + j)

I don't understand what you are

Previous: How does jquery catch select's value??

Next: Ask the seniors, the problem of an abnormal display of a broadcast picture in Google browser!

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
© 2021 CodesHelper
Advertising Contact us About us
Menu