Completed Roman Numeral.

Author: simdi

roman-numeral/index.js

@@ -0,0 +1,47 @@
+/*
+ * @author: Chisimdi Ezeanieto
+ * @date: 29/03/2023
+ * 
+ * @param {string} s
+ * @return {number}
+ */
+const symbolValue = {
+  "I": 1,
+  "V": 5,
+  "X": 10,
+  "L": 50,
+  "C": 100,
+  "D": 500,
+  "M": 1000
+};
+const romanToInt = function(s) {
+  // Convert each roman numeral to number and place each in an array.
+  const numbers = s.split('').reduce((curr, value) => {
+      curr.push(symbolValue[value]);
+      return curr;
+  }, []);
+  // Loop through the array and check if the current roman is greater than the next
+  let total = 0;
+  let i = 0;
+  
+  while (i < numbers.length) {
+      if (i < numbers.length - 1) {
+          if (numbers[i] > numbers[i + 1]) {
+            total += numbers[i];
+            i++;
+          } else if (numbers[i] === numbers[i+1]) {
+            total += (numbers[i + 1] + numbers[i]);
+            i+=2;
+          } else {
+            total += (numbers[i + 1] - numbers[i]);
+            i+=2;
+          }
+      } else {
+          total += numbers[i];
+          i++;
+      }
+  }
+  return total;
+};
+
+module.exports = romanToInt;

roman-numeral/test.js

@@ -0,0 +1,23 @@
+/*
+* @author: Chisimdi Damian Ezeanieto
+* @date: 16/03/2023
+*/
+const romanToInt = require('./index');
+
+describe('Phone key pad match', () => {
+  test('romanToInt function is defined', () => {
+    expect(typeof romanToInt).toEqual('function');
+  });
+  test('Convert roman to int for "I" === 1', () => {
+    expect(romanToInt('I')).toEqual(1);
+  });
+  test('Convert roman to int for "III" === 3', () => {
+    expect(romanToInt('III')).toEqual(3);
+  });
+  test('Convert roman to int for "LVIII" === 58', () => {
+    expect(romanToInt("LVIII")).toEqual(58);
+  });
+  test('Convert roman to int for "MCMXCIV" === 1994', () => {
+    expect(romanToInt("MCMXCIV")).toEqual(1994);
+  });
+});

string/reversestring/index.js

@@ -23,7 +23,7 @@ const reverseString = (str) => {
     // Switch positions as I loop through the string.
     // Big(O) = log N
     for (let i = 0; i < Math.floor(str.length/2); i++) {
-        [str[i], str[str.length-1-i]] = [str[str.length-1-i], str[i]];
+      [str[i], str[str.length-1-i]] = [str[str.length-1-i], str[i]];
     }
     return str.join('');
 };