diff --git a/src/binary-reversal/index.js b/src/binary-reversal/index.js
index 965bccf4..59ff3e78 100644
--- a/src/binary-reversal/index.js
+++ b/src/binary-reversal/index.js
@@ -3,6 +3,14 @@
  *
  *  * @param {string} value
  */
-function binaryReversal(value) {}
+function binaryReversal(value) {
+  let binaryNum = parseInt(value);
+  let binary = binaryNum.toString(2);
+  let padded = binary.padStart(8, "0");
+  let reversed = padded.split("").reverse().join("");
+  let result = parseInt(reversed, 2);
+  let finalResult = result.toString();
+  return finalResult;
+}
 
 module.exports = binaryReversal;
diff --git a/src/list-sorting/index.js b/src/list-sorting/index.js
index 6636c20d..dda2e48a 100644
--- a/src/list-sorting/index.js
+++ b/src/list-sorting/index.js
@@ -1,3 +1,43 @@
-function listSorting(needle, haystack) {}
+function listSorting(needle, haystack) {
+  if (haystack.length === 0) {
+    return -1
+  }
+
+  let event = 0;
+  for (let i = 0; i < haystack.length; i++) {
+    if (haystack[i] === needle) {
+      event++;
+    }
+  }
+
+  if (event === 0) {
+    return -1;
+  } else if (event === 1) {
+    return haystack.indexOf(needle)
+  } else {
+    return haystack.lastIndexOf(needle)
+  }
+
+  if (typeof (haystack[0]) === "object") {
+    let column
+    let row
+
+    for (let i = 0; i < haystack.length; i++) {
+      for (let j = 0; j < haystack[i].length; j++) {
+        if (haystack[i][j] === needle) {
+          column = haystack[i].lastIndexOf(needle)
+          row = i
+        }
+      }
+    }
+
+    if (row == undefined) return -1;
+    return [row, column]
+  } else {
+    return haystack.lastIndexOf(needle)
+
+  }
+}
 
 module.exports = listSorting;
+