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Mistake in test case Question #230

Open Eghizio opened this issue 3 years ago • 0 comments

There is a mistake in this question.

image

It is written that "{dklf(df(kl))d]{}" is a valid test case while it is not due to the not opened "[".

Please update the question.

The code I used to test the cases:

const sum = (arr: number[]): number => arr.reduce((acc, el) => acc+el, 0);

type OpeningBracket = "(" | "[" | "{";
type BracketStackMap = Record<OpeningBracket, number>;

const checkBrackets = (str: string) => {
  const brackets = ["(",")", "[","]", "{","}"]; // "()[]{}".split("");
  
  const filtered = str.split("").filter(character => brackets.includes(character));
  const bracketsStack = new Map<BracketStackMap>([["(", 0], ["[", 0], ["{", 0]]);

  for(let i=0; i<filtered.length; i++){
    // could be simplified with closed/opening bracket key/value mapping
    const key = filtered[i] === ")" ? "("
          : filtered[i] === "]" ? "["
          : filtered[i] === "}" ? "{"
          : filtered[i];
    
    const currentVal = bracketsStack.get(key);
    
    // console.log({i, str: filtered[i], key})
    
    switch(filtered[i]){
      case "(":
      case "[":
      case "{":
        bracketsStack.set(filtered[i], currentVal + 1);
        break;
      case ")":
      case "]":
      case "}":
        bracketsStack.set(key, currentVal - 1);
        break;
      default: throw new Error(`Unhandled bracket: ${filtered[i]}`);
    }
    
    if(bracketsStack.get(key) < 0){
      // console.log("negative", bracketsStack.get(key))
      return false;
    };
  }
  
  return (sum([...bracketsStack.values()]) === 0);
};

const tests = {
  "{ac[bb]}": true, 
  "{dklf(df(kl))d]{}": true, //fails, should pass according to task description
  "{[[[]]]}": true,
  "{3234[fd": false,
  "{df][d}": false
};

Object.entries(tests).forEach(([test, expected]) => {
  const result = (checkBrackets(test) === expected) ? "✅" : "❌";
  
  console.log(`${result} "${test}" `);
});
// results
"✅ '{ac[bb]}' "
"❌ '{dklf(df(kl))d]{}' "
"✅ '{[[[]]]}' "
"✅ '{3234[fd' "
"✅ '{df][d}' "

Eghizio avatar Jun 21 '21 03:06 Eghizio