michalmikolajczyk · January 8, 2015 22:11 · Jan 8, 2015
diff --git a/gistfile1.js b/gistfile1.js
@@ -0,0 +1,54 @@
+
+
+  var A = [];
+  A[0] = 3;
+  A[1] = 5;
+  A[2] = 6;
+  A[3] = 3;
+  A[4] = 3;
+  A[5] = 5;
+
+  function identicalIndices(someArray) {
+    var count = 0;
+    someArray.forEach(function (item, index) {
+      var restOfArray = someArray.slice(index + 1, someArray.length);
+      restOfArray.forEach(function (pairCandidate) {
+        if (pairCandidate === item) {
+          count++;
+        }
+      });
+
+    });
+
+    return count;
+  }
+
+  var b = identicalIndices(A);
+  console.log(b);
+
+}
+
+// Another way to do this is to create a helper object
+// which stores the indices like this
+// var helper = {};
+// var count = 0
+// A.forEach(function (item, index) {
+//   if (helper[item]) {
+//     helper[item].push(index);
+//   } else {
+//     helper[item] = [index];
+//   }
+// });
+
+// for (var key in helper) {
+//   if (helper.hasOwnProperty((key…
+
+
+      // if (helperObject[item]) {
+      //   helperObject[item]++;
+      //   if (helperObject[item] % 2 === 0) {
+      //     count++;
+      //   }
+      // } else {
+      //   helperObject[item] = 1;
+      // }