using recursion

realDuYuanChao · realDuYuanChao · commit d11b7347b650 · 2019-10-24T11:54:37.000+08:00
diff --git a/Maths/PowRecursion.java b/Maths/PowRecursion.java
@@ -17,10 +17,10 @@ public static void main(String[] args) {
      * @return the value {@code a}<sup>{@code b}</sup>.
      */
     public static long pow(int a, int b) {
-        int result = 1;
-        for (int i = 1; i <= b; i++) {
-            result *= a;
+        if (b == 0) {
+            return 1;
+        } else {
+            return a * pow(a, b - 1);
         }
-        return result;
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -17,10 +17,10 @@ public static void main(String[] args) {`
`17`	`17`	`* @return the value {@code a}<sup>{@code b}</sup>.`
`18`	`18`	`*/`
`19`	`19`	`public static long pow(int a, int b) {`
`20`		`- int result = 1;`
`21`		`- for (int i = 1; i <= b; i++) {`
`22`		`- result *= a;`
	`20`	`+ if (b == 0) {`
	`21`	`+ return 1;`
	`22`	`+ } else {`
	`23`	`+ return a * pow(a, b - 1);`
`23`	`24`	`}`
`24`		`- return result;`
`25`	`25`	`}`
`26`	`26`	`}`