Daily algorithm: Collating strings (queue characters in and out of the stack)

A, JS API

Math.abs(); // Get the absolute value
String.prototype.charCodeAt() // Get the character ASCII code value
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The ASCII code value of a character

'a'.charCodeAt() / / 97
'A'.charCodeAt() / / 65

'b'.charCodeAt() / / 98
'B'.charCodeAt() / / 66
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∴ a (1) when s[I] and S [i-1] are the same letter, and only one of them is ∴ B (2) :

 Math.abs(s[i].charCodeAt()-s[i-1].charCodeAt())===32
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The team included in the stack

var makeGood = function (str) {
 // Queue q holds the input and stack S holds the output
 let q = str.split(' '),s = [];
 
 // Iterate over the queue
 while (q.length) {
    
    // Queue character
    let curS = q.shift()

    // Queue characters ASCII
    let curV = curS.charCodeAt()
    
    // stack end character ASCII
    let preV = s[s.length - 1] && s[s.length - 1].charCodeAt()

    // If the queue character and the stack end character meet the requirements of the question, it needs to be deleted
    if (preV && Math.abs(curV - preV) === 32) {
      
      / / out of the stack
      s.pop()
    } else {

      / / into the stack
      s.push(curS)
    }
 }
 
/ / output
 return s.join(' ')}Copy the code