[BUGFIX] [REFACTOR] [Hacker Rank] Interview Preparation Kit: Recursion: Davis' Staircase.

Eslint issue eslint(no-param-reassign) fixed.

Author: Gonzalo Diaz

src/hackerrank/interview_preparation_kit/recursion_and_backtracking/ctci_recursive_staircase.js

@@ -5,30 +5,30 @@
 
 const TOP_LIMIT = 10 ** 10 + 7;
 const STEPS_LIMIT = 3;
+const CACHE = {};
 
-export function stepPermsComputWithCache(nSteps, cache, stepsLimit) {
+export function stepPermsComputWithCache(nSteps, stepsLimit) {
   if (nSteps >= 0 && nSteps <= 2) {
     return nSteps;
   }
 
-  const keys = new Set(Object.values(cache));
+  const keys = new Set(Object.keys(CACHE));
   let result = 0;
 
   for (let i = 1; i <= Math.min(stepsLimit, nSteps); i++) {
     const searchKey = nSteps - i;
     if (!keys.has(searchKey)) {
-      cache[searchKey] = stepPermsComputWithCache(searchKey, cache, stepsLimit);
+      CACHE[searchKey] = stepPermsComputWithCache(searchKey, stepsLimit);
     }
 
-    result += cache[searchKey];
+    result += CACHE[searchKey];
   }
 
   return result + (nSteps <= stepsLimit ? 1 : 0);
 }
 
 export function stepPerms(n) {
-  const initialCache = {};
-  return stepPermsComputWithCache(n, initialCache, STEPS_LIMIT) % TOP_LIMIT;
+  return stepPermsComputWithCache(n, STEPS_LIMIT) % TOP_LIMIT;
 }
 
 export default { stepPerms, stepPermsComputWithCache };

src/hackerrank/interview_preparation_kit/recursion_and_backtracking/ctci_recursive_staircase.test.js

@@ -28,15 +28,10 @@ describe('ctci_recursive_staircase', () => {
 
     TEST_CASES_GENERALIZED.forEach((testSet) => {
       testSet?.tests.forEach((test) => {
-        const initialCache = {};
-        const answer = stepPermsComputWithCache(
-          test.input,
-          initialCache,
-          test.limit
-        );
+        const answer = stepPermsComputWithCache(test.input, test.limit);
 
         console.debug(
-          `stepPermsComputWithCache(${test.input}, ${initialCache}, ${test.limit}) solution found: ${answer}`
+          `stepPermsComputWithCache(${test.input}, ${test.limit}) solution found: ${answer}`
         );
 
         expect(answer).toStrictEqual(test.expected);