Fix

begeekmyfriend · begeekmyfriend · commit 042fe663a587 · 2020-06-22T22:34:12.000+08:00
Signed-off-by: begeekmyfriend &lt;begeekmyfriend@gmail.com&gt;
diff --git a/020_valid_parentheses/valid_parentheses.c b/020_valid_parentheses/valid_parentheses.c
@@ -4,28 +4,24 @@
 
 static bool isValid(char *s)
 {
-    int n = 0, cap = 100;
-    char *stack = malloc(cap);
+    int n = 0;
+    char stack[100];
 
     while (*s != '\0') {
         switch(*s) {
         case '(':
         case '[':
         case '{':
-            if (n + 1 >= cap) {
-                cap *= 2;
-                stack = realloc(stack, cap);
-            }
             stack[n++] = *s;
             break;
         case ')':
-            if (stack[--n] != '(') return false;
+            if (n == 0 || stack[--n] != '(') return false;
             break;
         case ']':
-            if (stack[--n] != '[') return false;
+            if (n == 0 || stack[--n] != '[') return false;
             break;
         case '}':
-            if (stack[--n] != '{') return false;
+            if (n == 0 || stack[--n] != '{') return false;
             break;
         default:
             return false;
