Biginteger/decimal

2026-08-16 14:55:25 +08:00
parent abd82e6961
commit 5b3320e65c
8 changed files with 975 additions and 6 deletions
@@ -0,0 +1,72 @@
+#pragma once
+
+#include <string>
+#include "BigInteger.hpp"
+
+namespace bstl {
+
+class BigDecimal {
+public:
+    BigDecimal();
+    BigDecimal(int value);
+    BigDecimal(long long value);
+    BigDecimal(double value);
+    explicit BigDecimal(const std::string& value);
+    explicit BigDecimal(const char* value);
+    BigDecimal(const BigInteger& unscaledValue, int scale);
+    BigDecimal(const BigDecimal& other) = default;
+    BigDecimal& operator=(const BigDecimal& other) = default;
+
+    bool isZero() const;
+    int sign() const;
+    int getScale() const;
+    BigInteger getUnscaledValue() const;
+    std::string toString() const;
+
+    // Comparison operators
+    bool operator==(const BigDecimal& other) const;
+    bool operator!=(const BigDecimal& other) const;
+    bool operator<(const BigDecimal& other) const;
+    bool operator>(const BigDecimal& other) const;
+    bool operator<=(const BigDecimal& other) const;
+    bool operator>=(const BigDecimal& other) const;
+
+    bool operator==(int value) const;
+    bool operator!=(int value) const;
+    bool operator<(int value) const;
+    bool operator>(int value) const;
+    bool operator<=(int value) const;
+    bool operator>=(int value) const;
+
+    bool operator==(double value) const;
+    bool operator!=(double value) const;
+    bool operator<(double value) const;
+    bool operator>(double value) const;
+    bool operator<=(double value) const;
+    bool operator>=(double value) const;
+
+    // Arithmetic operators
+    BigDecimal operator+() const;
+    BigDecimal operator-() const;
+    BigDecimal& operator+=(const BigDecimal& other);
+    BigDecimal& operator-=(const BigDecimal& other);
+    BigDecimal& operator*=(const BigDecimal& other);
+    BigDecimal& operator/=(const BigDecimal& other);
+
+    BigDecimal operator+(const BigDecimal& other) const;
+    BigDecimal operator-(const BigDecimal& other) const;
+    BigDecimal operator*(const BigDecimal& other) const;
+    BigDecimal operator/(const BigDecimal& other) const;
+
+    BigDecimal abs() const;
+    BigDecimal round(int scale) const;
+
+private:
+    BigInteger unscaledValue_;  // 去掉小数点后的值
+    int scale_;                 // 小数点后的位数
+
+    static void alignScale(BigInteger& lhs, int& lhsScale,
+                          BigInteger& rhs, int& rhsScale);
+};
+
+} // namespace bstl