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/**
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* File: max_product_cutting.dart
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* Created Time: 2023-08-11
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* Author: liuyuxin (gvenusleo@gmail.com)
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*/
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import 'dart:math';
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/* 最大切分乘积：贪心 */
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int maxProductCutting(int n) {
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// 当 n <= 3 时，必须切分出一个 1
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if (n <= 3) {
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return 1 * (n - 1);
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}
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// 贪心地切分出 3 ，a 为 3 的个数，b 为余数
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int a = n ~/ 3;
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int b = n % 3;
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if (b == 1) {
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// 当余数为 1 时，将一对 1 * 3 转化为 2 * 2
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return (pow(3, a - 1) * 2 * 2).toInt();
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}
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if (b == 2) {
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// 当余数为 2 时，不做处理
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return (pow(3, a) * 2).toInt();
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}
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// 当余数为 0 时，不做处理
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return pow(3, a).toInt();
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}
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/* Driver Code */
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void main() {
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int n = 58;
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// 贪心算法
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int res = maxProductCutting(n);
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print("最大切分乘积为 $res");
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}
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