add Problem05

realDuYuanChao · realDuYuanChao · commit d9b365bcd9c1 · 2020-10-05T15:33:27.000+08:00
diff --git a/src/main/java/com/examplehub/projecteuler/Problem05.java b/src/main/java/com/examplehub/projecteuler/Problem05.java
@@ -0,0 +1,24 @@
+package com.examplehub.projecteuler;
+
+/**
+ * 2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.
+ * <p>
+ * What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?
+ * <p>
+ * link: https://projecteuler.net/problem=5
+ */
+public class Problem05 {
+
+    public static long solution1(int n) {
+        for (int i = n; ; i++) {
+            for (int j = 1; j <= n; j++) {
+                if (i % j != 0) {
+                    break;
+                }
+                if (j == n) {
+                    return i;
+                }
+            }
+        }
+    }
+}
diff --git a/src/test/java/com/examplehub/projecteuler/Problem05Test.java b/src/test/java/com/examplehub/projecteuler/Problem05Test.java
@@ -0,0 +1,14 @@
+package com.examplehub.projecteuler;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class Problem05Test {
+    @Test
+    void testSolution1() {
+        assertEquals(2520, Problem05.solution1(10));
+        assertEquals(360360, Problem05.solution1(15));
+        assertEquals(232792560, Problem05.solution1(20));
+    }
+}
