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package g0901_1000.s0972_equal_rational_numbers;

// #Hard #String #Math #2022_03_31_Time_4_ms_(56.67%)_Space_43.5_MB_(6.67%)

/**
 * 972 - Equal Rational Numbers\.
 *
 * Hard
 *
 * Given two strings `s` and `t`, each of which represents a non-negative rational number, return `true` if and only if they represent the same number. The strings may use parentheses to denote the repeating part of the rational number.
 *
 * A **rational number** can be represented using up to three parts: `<IntegerPart>`, `<NonRepeatingPart>`, and a `<RepeatingPart>`. The number will be represented in one of the following three ways:
 *
 * *   `<IntegerPart>`
 *     *   For example, `12`, `0`, and `123`.
 * *   `<IntegerPart>**<.>**<NonRepeatingPart>`
 *     *   For example, `0.5`, `1.`, `2.12`, and `123.0001`.
 * *   `<IntegerPart>**<.>**<NonRepeatingPart>**<(>**<RepeatingPart>**<)>**`
 *     *   For example, `0.1(6)`, `1.(9)`, `123.00(1212)`.
 *
 * The repeating portion of a decimal expansion is conventionally denoted within a pair of round brackets. For example:
 *
 * *   `1/6 = 0.16666666... = 0.1(6) = 0.1666(6) = 0.166(66)`.
 *
 * **Example 1:**
 *
 * **Input:** s = "0.(52)", t = "0.5(25)"
 *
 * **Output:** true
 *
 * **Explanation:** Because "0.(52)" represents 0.52525252..., and "0.5(25)" represents 0.52525252525..... , the strings represent the same number.
 *
 * **Example 2:**
 *
 * **Input:** s = "0.1666(6)", t = "0.166(66)"
 *
 * **Output:** true
 *
 * **Example 3:**
 *
 * **Input:** s = "0.9(9)", t = "1."
 *
 * **Output:** true
 *
 * **Explanation:** "0.9(9)" represents 0.999999999... repeated forever, which equals
 *
 * 1. [[See this link for an explanation.](https://en.wikipedia.org/wiki/0.999...)] "1." represents the number 1, which is formed correctly: (IntegerPart) = "1" and (NonRepeatingPart) = "".
 *
 * **Constraints:**
 *
 * *   Each part consists only of digits.
 * *   The `<IntegerPart>` does not have leading zeros (except for the zero itself).
 * *   `1 <= <IntegerPart>.length <= 4`
 * *   `0 <= <NonRepeatingPart>.length <= 4`
 * *   `1 <= <RepeatingPart>.length <= 4`
**/
public class Solution {
    public boolean isRationalEqual(String s, String t) {
        int sLeftIndex = s.indexOf("(");
        int tLeftIndex = t.indexOf("(");
        // if they are integer or only with non repeating part
        if (sLeftIndex < 0 && tLeftIndex < 0) {
            return Double.valueOf(s).equals(Double.valueOf(t));
        }
        // get the first 100 (or so) digits of s and t
        double sDouble;
        double tDouble;
        if (sLeftIndex >= 0) {
            s = s.substring(0, sLeftIndex) + repeat(s.substring(sLeftIndex + 1, s.length() - 1));
            sDouble = Double.parseDouble(s.substring(0, 100));
        } else {
            sDouble = Double.parseDouble(s);
        }
        if (tLeftIndex >= 0) {
            t = t.substring(0, tLeftIndex) + repeat(t.substring(tLeftIndex + 1, t.length() - 1));
            tDouble = Double.parseDouble(t.substring(0, 100));
        } else {
            tDouble = Double.parseDouble(t);
        }
        return sDouble == tDouble;
    }

    private String repeat(String a) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < 100; i++) {
            sb.append(a);
        }
        return sb.toString();
    }
}