Changed name of stretch assigment file and put it in folder

Author: Wayleom Vargas Rubio

lesson_06/expression/src/wayleomvargas/abbreviation-validator.ts

@@ -0,0 +1,24 @@
+export function isValidAlphaAbbreviation(word: string, abbr: string): boolean {
+    if (word.length < 1 || word.length > 25) return false;
+    if (abbr.length < 1 || abbr.length > 15) return false;
+    if (!/^[a-z]+$/.test(word)) return false;
+    if (!/^[a-z]+$/.test(abbr)) return false;
+    
+    let wordIndex = 0;
+    let i = 0;
+    
+    while (i < abbr.length && wordIndex < word.length) {
+        const ch: string = abbr[i];
+        
+        if (word[wordIndex] === ch) {
+            wordIndex++;
+            i++;
+        } else {
+            const skip: number = ch.charCodeAt(0) - 96;
+            wordIndex += skip;
+            i++;
+        }
+    }
+    
+    return wordIndex === word.length && i === abbr.length;
+}