Package g1801_1900.s1896_minimum_cost_to_change_the_final_value_of_expression

Class Solution

java.lang.Object
g1801_1900.s1896_minimum_cost_to_change_the_final_value_of_expression.Solution
public class Solution extends Object
1896 - Minimum Cost to Change the Final Value of Expression\. Hard You are given a **valid** boolean expression as a string `expression` consisting of the characters `'1'`,`'0'`,`'&'` (bitwise **AND** operator),`'|'` (bitwise **OR** operator),`'('`, and `')'`. * For example, `"()1|1"` and `"(1)&()"` are **not valid** while `"1"`, `"(((1))|(0))"`, and `"1|(0&(1))"` are **valid** expressions. Return _the **minimum cost** to change the final value of the expression_. * For example, if `expression = "1|1|(0&0)&1"`, its **value** is `1|1|(0&0)&1 = 1|1|0&1 = 1|0&1 = 1&1 = 1`. We want to apply operations so that the **new** expression evaluates to `0`. The **cost** of changing the final value of an expression is the **number of operations** performed on the expression. The types of **operations** are described as follows: * Turn a `'1'` into a `'0'`. * Turn a `'0'` into a `'1'`. * Turn a `'&'` into a `'|'`. * Turn a `'|'` into a `'&'`. **Note:** `'&'` does **not** take precedence over `'|'` in the **order of calculation**. Evaluate parentheses **first** , then in **left-to-right** order. **Example 1:** **Input:** expression = "1&(0|1)" **Output:** 1 **Explanation:** We can turn "1&(0|1)" into "1&(0&1)" by changing the '|' to a '&' using 1 operation. The new expression evaluates to 0. **Example 2:** **Input:** expression = "(0&0)&(0&0&0)" **Output:** 3 **Explanation:** We can turn "(0&0)&(0&0&0)" into "(0|1)|(0&0&0)" using 3 operations. The new expression evaluates to 1. **Example 3:** **Input:** expression = "(0|(1|0&1))" **Output:** 1 **Explanation:** We can turn "(0|(1|0&1))" into "(0|(0|0&1))" using 1 operation. The new expression evaluates to 0. **Constraints:** * 1 <= expression.length <= 105 * `expression` only contains `'1'`,`'0'`,`'&'`,`'|'`,`'('`, and `')'` * All parentheses are properly matched. * There will be no empty parentheses (i.e: `"()"` is not a substring of `expression`).

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • minOperationsToFlip

      public int minOperationsToFlip(String expression)