refactor: update FastPower

src/test/java/com/others/FastPowerTest.java

@@ -1,9 +1,35 @@
 package src.test.java.com.others;
 
-/**
+import org.junit.Test;
- * @author bingo
+import src.main.java.com.others.FastPower;
- * @since 2019/5/10
+
- */
+import java.math.BigInteger;
+
+import static org.junit.Assert.*;
 
 public class FastPowerTest {
+
+    @Test
+    void testLong(long n, long k, long m) {
+        long result = FastPower.calculate(n, k, m);
+        assertEquals(result, BigInteger.valueOf(n).modPow(BigInteger.valueOf(k), BigInteger.valueOf(m)).longValue());
+    }
+
+    @Test
+    void testBigInteger(BigInteger n, BigInteger k, BigInteger m) {
+        BigInteger result = FastPower.calculate(n, k, m);
+        assertEquals(result, n.modPow(k, m));
+    }
+
+    @Test
+    public void test() {
+        testLong(2, 2, 10);
+        testLong(100, 1000, 20);
+        testLong(123456, 123456789, 234);
+
+        testBigInteger(BigInteger.TEN, BigInteger.TEN, BigInteger.valueOf(4));
+        testBigInteger(new BigInteger("123456"), new BigInteger("123456789"), new BigInteger("234"));
+        testBigInteger(new BigInteger("123456789101112"), new BigInteger("12345678910111213"), new BigInteger("567890"));
+
+    }
 }