Emmanuel o. olokor

src/binary-reversal/index.js

@@ -3,6 +3,39 @@
  *
  *  * @param {string} value
  */
-function binaryReversal(value) {}
+  function binaryReversal(value) {
+    let loop = Math.floor(value ** 0.5) + 1;
+    let arr = [];
+    for (let i = 0; i < loop; i++) {
+      if (value > 1) {
+        arr.push(value % 2);
+        value = Math.floor(value / 2);
+      } else if (value == 1) {
+        arr.push(1);
+        value = 0;
+      }
+    }
+    let strNum = arr.join("");
+    let length = strNum.length;
+
+    let n8 = Math.ceil(length / 8);
+
+    if (length < 8 * n8) {
+      let diff = 8 * n8 - strNum.length;
+
+      for (let i = 0; i < diff; i++) {
+        strNum += "0";
+      }
+    }
+    let newLength = strNum.length;
+
+    let sumArray = [];
+    for (let i = 0; i < newLength; i++) {
+      let pow = newLength - 1 - i;
+      let num = strNum[i];
+      sumArray.push(num * 2 ** pow);
+    }
+    return sumArray.reduce((a, b) => a + b).toString();
+  }
 
 module.exports = binaryReversal;

src/list-sorting/index.js

@@ -1,3 +1,33 @@
-function listSorting(needle, haystack) {}
+function listSorting(needle, haystack) {
+
+    if (haystack.length == 0) return -1;
+    let arr = [];
+
+    if (typeof haystack[0] == "object") {
+      for (let i = 0; i < haystack.length; i++) {
+        if (haystack[i].length != 0 && haystack[i].lastIndexOf(needle) != -1) {
+          arr.push(haystack[i].lastIndexOf(needle));
+        } else {
+          arr.push(null);
+        }
+      }
+      if (arr.every((el) => el == null)) return -1;
+
+
+      let arr2 = [];
+
+      for (let i = 0; i < arr.length; i++) {
+        let arr1 = [];
+        if (typeof arr[i] == "number") {
+          arr1.push(arr.lastIndexOf(arr[i]), arr[i]);
+        } else continue;
+        arr2.push(arr1);
+      }
+      if (arr2.length == 0) return -1;
+      return arr2[arr2.length - 1];
+    } else if (typeof haystack[0] == "number") {
+      return haystack.lastIndexOf(needle);
+    }
+}
 
 module.exports = listSorting;