From e74f5a31bd6856d8c64987742cda6b3882952636 Mon Sep 17 00:00:00 2001
From: Hatter Jiang <jht5945@gmail.com>
Date: Sun, 7 Sep 2025 15:16:27 +0800
Subject: [PATCH] feat: add euler constant - gamma

---
 src/main/java/me/hatter/math/util/MathUtil.java | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/main/java/me/hatter/math/util/MathUtil.java b/src/main/java/me/hatter/math/util/MathUtil.java
index 2e7cb41..03c664c 100644
--- a/src/main/java/me/hatter/math/util/MathUtil.java
+++ b/src/main/java/me/hatter/math/util/MathUtil.java
@@ -6,6 +6,7 @@ import java.math.RoundingMode;
 
 public class MathUtil {
 
+    // 欧拉数（Euler Number）
     public static final BigDecimal E = new BigDecimal(
             "2.7182818284590452353602874713526624977572470936999595749669676277240766303535475945713821785251664238"
     );
@@ -18,6 +19,12 @@ public class MathUtil {
             "1.6180339887498948482045868343656381177203091798057628621354486227052604628189024497072072041893911375"
     );
 
+    // 欧拉-马歇罗尼常数(Euler-Mascheroni constant)
+    // https://hatter.ink/static/resource/muboard/?id=eulers-constant&version=latest&full=1
+    public static final BigDecimal GAMMA = new BigDecimal(
+            "0.5772156649015328606065120900824024310421593359399235988057672348848677267776646709369470632917467495"
+    );
+
     public static final BigDecimal LITTLE_NUMBER = new BigDecimal(
             "0.000000000000000000000000000000000000000001");