add some problems

5.4ArrayMethod/t.js

@@ -77,3 +77,25 @@ console.log(`nameLists: ${nameLists.join('; ')}`)
 // [LOG - 6/16/24 21:33:45] "nameLists: Bilbo; Gandalf"
 
 
+// arr.reduce(fn) arr.reduceRight(fn)
+let numbers = [1,2,3,4,5]
+console.log(numbers.reduce(function(sum, current){
+    return sum + current;
+}, 0));
+console.log(numbers.reduce((sum, cur) => sum + cur, 0));
+console.log(numbers.reduceRight((sum, cur) => sum + cur, 0));
+
+// Array.isArray()
+console.log(Array.isArray(countries))
+
+function camelize(str){
+    words = str.split('-')
+    for(let i = 1; i < words.length; i++){
+        words[i][0] = words[i][0].toUpperCase();
+        console.log(words[i])
+    }
+    return words.join('');
+}
+console.log(camelize("background-color"))
+console.log(camelize("list-style-image"))
+console.log(camelize("-webkit-translation"))