36 lines
908 B
Java
36 lines
908 B
Java
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//实现 pow(x, n) ，即计算 x 的 n 次幂函数（即，x⁴
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//
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// Related Topics 递归 数学 👍 718 👎 0
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package leetcode.editor.cn;
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//50:Pow(x, n)
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class PowxN {
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public static void main(String[] args) {
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//测试代码
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Solution solution = new PowxN().new Solution();
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}
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//力扣代码
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//leetcode submit region begin(Prohibit modification and deletion)
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class Solution {
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public double myPow(double x, int n) {
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double ans = 1;
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if (n < 0) {
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x = 1 / x;
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}
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long exp = n;
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exp = Math.abs(exp);
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while (exp > 0) {
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if (exp % 2 == 1) {
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ans = ans * x;
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}
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x *= x;
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exp /= 2;
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}
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return ans;
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}
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}
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//leetcode submit region end(Prohibit modification and deletion)
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}
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