wip

exercises/18_iterators/iterators2.rs

@@ -6,17 +6,18 @@
 // Execute `rustlings hint iterators2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 // Step 1.
 // Complete the `capitalize_first` function.
 // "hello" -> "Hello"
 pub fn capitalize_first(input: &str) -> String {
     let mut c = input.chars();
-    match c.next() {
+    let cap = match c.next() {
         None => String::new(),
-        Some(first) => ???,
-    }
+        Some(first) => first.to_uppercase().to_string(),
+    };
+    let rest: String = c.collect();
+
+    format!("{cap}{rest}")
 }
 
 // Step 2.
@@ -24,7 +25,7 @@ pub fn capitalize_first(input: &str) -> String {
 // Return a vector of strings.
 // ["hello", "world"] -> ["Hello", "World"]
 pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
-    vec![]
+    words.iter().map(|f| capitalize_first(f)).collect()
 }
 
 // Step 3.
@@ -32,7 +33,7 @@ pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
 // Return a single string.
 // ["hello", " ", "world"] -> "Hello World"
 pub fn capitalize_words_string(words: &[&str]) -> String {
-    String::new()
+    words.iter().map(|f| capitalize_first(f)).collect()
 }
 
 #[cfg(test)]