count pairs

Author: manju07

Data-Structure/Hashing/countPairs.js

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+'use strict';
+function countPairsDivideOneElement(array) {
+    let hm = new Map();
+    let maxValue = -Infinity;
+    let countPairs = 0;
+    for (let index = 0; index < array.length; index++) {
+        if (maxValue < array[index]) maxValue = array[index];
+        hm.set(array[index]);
+    }
+    for (let index = 0; index < array.length; index++) {
+        let multiply = 2;
+        let k = array[index] * multiply;
+        while (k <= maxValue) {
+            if (hm.has(k)) countPairs++;
+            k = array[index] * (++multiply);
+        }
+    }
+    return countPairs;
+}
+let array = [1, 2, 3];
+console.log('Number of pairs that one element of pair divides other = ', countPairsDivideOneElement(array));