BAEL-3481

2019-12-03 15:29:04 +05:30
parent ac357ee98c
commit b333276281
4 changed files with 244 additions and 0 deletions
@@ -0,0 +1,47 @@
+package com.baeldung.algorithms.balancedbrackets;
+
+import java.util.Stack;
+
+public class BalancedBracketsUsingStack {
+
+        public boolean isBalanced(String str) {
+                boolean result = true;
+
+                if (null == str || str.length() == 0 || ((str.length() % 2) != 0)) {
+                        result = false;
+                } else {
+                        char[] ch = str.toCharArray();
+                        for (char c : ch) {
+                                if (!(c == '{' || c == '[' || c == '(' || c == '}' || c == ']' || c == ')')) {
+                                        result = false;
+                                        break;
+                                }
+
+                        }
+                }
+
+                if(result) {
+                        Stack<Character> stack = new Stack<>();
+                        for (char ch: str.toCharArray()) {
+                                if (ch == '{' || ch == '[' || ch == '(') {
+                                        stack.push(ch);
+                                } else {
+                                        if ( !stack.isEmpty()
+                                                && ((stack.peek() == '{' && ch == '}')
+                                                || (stack.peek() == '[' && ch == ']')
+                                                || (stack.peek() == '(' && ch == ')')
+                                            )) {
+                                                stack.pop();
+                                                result = true;
+                                        } else {
+                                                result = false;
+                                                break;
+                                        }
+                                }
+
+                        }
+                }
+
+                return result;
+        }
+}
@@ -0,0 +1,37 @@
+package com.baeldung.algorithms.balancedbrackets;
+
+public class BalancedBracketsUsingString {
+
+        public boolean isBalanced(String str) {
+                boolean result = true;
+
+                if (null == str || str.length() == 0 || ((str.length() % 2) != 0)) {
+                        result = false;
+                } else {
+                        char[] ch = str.toCharArray();
+                        for(char c : ch) {
+                                if(!(c == '{' || c == '[' || c == '(' || c == '}' || c == ']' || c == ')')) {
+                                        result = false;
+                                        break;
+                                }
+
+                        }
+                }
+
+                if (result) {
+                        while (str.indexOf("()") >= 0 || str.indexOf("[]") >= 0 || str.indexOf("{}") >= 0) {
+                                str = str.replaceAll("\\(\\)", "")
+                                    .replaceAll("\\[\\]", "")
+                                    .replaceAll("\\{\\}", "");
+                        }
+                        if (str.length() > 0) {
+                                result = false;
+                        } else {
+                                result = true;
+                        }
+                }
+
+                return result;
+        }
+
+}