I have this simple JS task that i can't figure out, not so simple for me after all.
Create a function 'converter', that converts letters in this way:
T -> C
C -> T
A -> D
X -> Y
Function accepts String with letters. All non convertable letters should be removed from string.
Example:
- converter('TTCCAAXX') -> 'CCTTDDYY'
- converter('TTGG') -> 'CC'
I tried something like this -
function Converter(str) {
let upperStr = str.toUpperCase()
let newStr = upperStr.replaceAll("T", "C").replaceAll("C", "T")
console.log(newStr)
}
Converter("TTCCAAXX")
But this is replacing all the characters and overwriting them and I'm not getting the right results.
You need to use a sequential for loop which is more efficient (only requires one iteration) and solves the overwriting issue.
For better flexibility we can store the character pairs in an object.
const convertKeyValue = {
'T': 'C',
'C': 'T',
'A': 'D',
'X': 'Y'
}
function Converter(str) {
let upperStr = str.toUpperCase()
var newStr = ''
for(let i = 0; i < upperStr.length; i++){
const current = upperStr.charAt(i);
newStr += convertKeyValue[current] ? convertKeyValue[current] : '';
}
return newStr;
}
console.log(Converter('TTCCAAXX'));
console.log(Converter('TTGG'));Consider adding a boolean/counter to represent the state in addition to new mappings. That way you don't get recurring or cyclical conversions.