optimizations

day5/src/main.rs

@@ -24,42 +24,22 @@ fn main() {
 }
 
 fn reduce(string: String) -> i32 {
-    let mut current_string = string;
-    let mut new_string: Vec<char>;
-    let mut last_string = String::new();
+    let all_chars: Vec<char> = string.chars().into_iter().collect();
 
-    while last_string != current_string {
-        let all_chars: Vec<char> = current_string.chars().into_iter().collect();
-        let mut count = 0;
+    let mut stack: Vec<char> = Vec::new();
 
-        new_string = Vec::new();
-
-        while count < all_chars.len() - 1 {
-            let cur_char_uppercase = all_chars[count].to_uppercase().collect::<Vec<char>>()[0];
-            let cur_char_lowercase = all_chars[count].to_lowercase().collect::<Vec<char>>()[0];
-
-            if all_chars[count] == cur_char_lowercase {
-                if all_chars[count + 1] == cur_char_uppercase{
-                    count += 1;
-                } else {
-                    new_string.push(all_chars[count].clone());
-                }
-            } else {
-                if all_chars[count + 1] == cur_char_lowercase{
-                    count += 1;
-                } else {
-                    new_string.push(all_chars[count].clone());
-                }
+    for c in all_chars{
+        if !stack.is_empty(){
+            let sub = *stack.last().unwrap() as i32 - c as i32;
+            if sub == 32 || sub == -32 {
+                stack.pop();
+            } else{
+                stack.push(c.clone());
             }
-
-            count += 1;
+        } else {
+            stack.push(c.clone());
         }
-
-        new_string.push(all_chars[all_chars.len() - 1].clone());
-
-        last_string= current_string.clone();
-        current_string = new_string.clone().into_iter().collect();
     }
 
-    return (current_string.len()-1) as i32
-}
+    return stack.len() as i32
+}