在此程序中，您將學(xué)習(xí)如何使用Java中的遞歸函數(shù)來計(jì)算數(shù)字的冪。
public class Power {
public static void main(String[] args) {
int base = 3, powerRaised = 4;
int result = power(base, powerRaised);
System.out.printf("%d^%d = %d", base, powerRaised, result);
}
public static int power(int base, int powerRaised) {
if (powerRaised != 0)
return (base * power(base, powerRaised - 1));
else
return 1;
}
}運(yùn)行該程序時(shí)，輸出為：
3^4 = 81
在上面的程序中，您使用遞歸函數(shù)power()計(jì)算冪。
簡單地說，遞歸函數(shù)將底數(shù)與自身相乘，以獲得提升次數(shù)，即：
3 * 3 * 3 * 3 = 81
| Iteration | power() | powerRaised | result |
|---|---|---|---|
| 1 | power(3, 4) | 4 | 3 * result2 |
| 2 | power(3, 3) | 3 | 3 * 3 * result3 |
| 3 | power(3, 2) | 2 | 3 * 3 * 3 * result4 |
| 4 | power(3, 1) | 1 | 3 * 3 * 3 * 3 * resultfinal |
| Final | power(3, 0) | 0 | 3 * 3 * 3 * 3 * 1 = 81 |