recursion reacto

reacto/recursion_one.js

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+// Prompt
+// Write a function "reverseString" that takes a string as input, and returns that string reversed. You MUST use recursion for your answer. Any form of looping (including built-ins like .forEach) are forbidden for your solution.
+
+// hello
+// ello
+// llo
+// lo
+// o
+// ''
+// ''
+
+const reverseString = (inputString) => {
+    console.log('Going Down: ', inputString);
+
+    // Base Case - Where do we stop calling ourselves again?
+    if (inputString.length === 0) {
+        return '';
+    }
+    // Recursive Case - When do we call ourselves again?
+    const restOfCharactersReversed = reverseString(inputString.substring(1, inputString.length));
+    console.log('Result of Reversal While Coming Up: ', restOfCharactersReversed);
+
+    // Return - How do we create the value over time?
+    return restOfCharactersReversed + inputString[0];
+}
+
+console.log(reverseString('hello')); // => olleh
+
+
+
+
+
+
+
+
+
+
+
+
+// Solution
+// const reverseString = (inputString) => {
+//     // Base Case: Return nothing if there are no characters left.
+//     if (inputString.length === 0) {
+//         return '';
+//     }
+//
+//     // Recursive Case: Reverse every character in the string besides for the first one.
+//     const restOfStringReversed = reverseString(
+//         inputString.substring(1, inputString.length),
+//     );
+//
+//     // Because, we will append whatever the "first" character was at this level to the end of the rest of the string reversed.
+//     return restOfStringReversed + inputString.charAt(0);
+// };
+//
+// console.log(reverseString('hello')); // => olleh