标签:arr end int System aim start 动态 规划
package advanced_class_06; public class Code_01_CoinsWay { public static int coins1(int[] arr, int aim) { if (arr == null || arr.length == 0 || aim < 0) { return 0; } return process1(arr, 0, aim); } public static int process1(int[] arr, int index, int aim) { int res = 0; if (index == arr.length) { res = aim == 0 ? 1 : 0; } else { for (int i = 0; arr[index] * i <= aim; i++) { res += process1(arr, index + 1, aim - arr[index] * i); } } return res; } /** * * @param arr * @param index * @param aim * @return */ public static int process2(int[] arr, int index, int aim) { int res = 0; if (arr.length == index) { res = aim == 0 ? 1 : 0; } else { for (int i = 0; arr[index] * i <= aim; i++) { res += process2(arr, index + 1, aim - arr[index] * i); } } return res; } public static int coinsOther(int[] arr, int aim) { if (arr == null || arr.length == 0 || aim < 0) { return 0; } return processOther(arr, arr.length - 1, aim); } public static int processOther(int[] arr, int index, int aim) { int res = 0; if (index == -1) { res = aim == 0 ? 1 : 0; } else { for (int i = 0; arr[index] * i <= aim; i++) { res += processOther(arr, index - 1, aim - arr[index] * i); } } return res; } public static int coins2(int[] arr, int aim) { if (arr == null || arr.length == 0 || aim < 0) { return 0; } int[][] map = new int[arr.length + 1][aim + 1]; return process2(arr, 0, aim, map); } public static int process2(int[] arr, int index, int aim, int[][] map) { int res = 0; if (index == arr.length) { res = aim == 0 ? 1 : 0; } else { int mapValue = 0; for (int i = 0; arr[index] * i <= aim; i++) { mapValue = map[index + 1][aim - arr[index] * i]; if (mapValue != 0) { res += mapValue == -1 ? 0 : mapValue; } else { res += process2(arr, index + 1, aim - arr[index] * i, map); } } } map[index][aim] = res == 0 ? -1 : res; return res; } public static int coins3(int[] arr, int aim) { if (arr == null || arr.length == 0 || aim < 0) { return 0; } int[][] dp = new int[arr.length][aim + 1]; for (int i = 0; i < arr.length; i++) { dp[i][0] = 1; } for (int j = 1; arr[0] * j <= aim; j++) { dp[0][arr[0] * j] = 1; } int num = 0; for (int i = 1; i < arr.length; i++) { for (int j = 1; j <= aim; j++) { num = 0; for (int k = 0; j - arr[i] * k >= 0; k++) { num += dp[i - 1][j - arr[i] * k]; } dp[i][j] = num; } } return dp[arr.length - 1][aim]; } public static int coins4(int[] arr, int aim) { if (arr == null || arr.length == 0 || aim < 0) { return 0; } int[][] dp = new int[arr.length][aim + 1]; for (int i = 0; i < arr.length; i++) { dp[i][0] = 1; } for (int j = 1; arr[0] * j <= aim; j++) { dp[0][arr[0] * j] = 1; } for (int i = 1; i < arr.length; i++) { for (int j = 1; j <= aim; j++) { dp[i][j] = dp[i - 1][j]; dp[i][j] += j - arr[i] >= 0 ? dp[i][j - arr[i]] : 0; } } return dp[arr.length - 1][aim]; } public static int coins5(int[] arr, int aim) { if (arr == null || arr.length == 0 || aim < 0) { return 0; } int[] dp = new int[aim + 1]; for (int j = 0; arr[0] * j <= aim; j++) { dp[arr[0] * j] = 1; } for (int i = 1; i < arr.length; i++) { for (int j = 1; j <= aim; j++) { dp[j] += j - arr[i] >= 0 ? dp[j - arr[i]] : 0; } } return dp[aim]; } public static void main(String[] args) { int[] coins = { 10, 5, 1, 25 }; int aim = 2000; long start = 0; long end = 0; start = System.currentTimeMillis(); System.out.println(coins1(coins, aim)); end = System.currentTimeMillis(); System.out.println("cost time : " + (end - start) + "(ms)"); start = System.currentTimeMillis(); System.out.println(coinsOther(coins, aim)); end = System.currentTimeMillis(); System.out.println("cost time : " + (end - start) + "(ms)"); aim = 20000; start = System.currentTimeMillis(); System.out.println(coins2(coins, aim)); end = System.currentTimeMillis(); System.out.println("cost time : " + (end - start) + "(ms)"); start = System.currentTimeMillis(); System.out.println(coins3(coins, aim)); end = System.currentTimeMillis(); System.out.println("cost time : " + (end - start) + "(ms)"); start = System.currentTimeMillis(); System.out.println(coins4(coins, aim)); end = System.currentTimeMillis(); System.out.println("cost time : " + (end - start) + "(ms)"); start = System.currentTimeMillis(); System.out.println(coins5(coins, aim)); end = System.currentTimeMillis(); System.out.println("cost time : " + (end - start) + "(ms)"); } }
标签:arr,end,int,System,aim,start,动态,规划 来源: https://www.cnblogs.com/cyy3900/p/14854702.html
本站声明: 1. iCode9 技术分享网(下文简称本站)提供的所有内容,仅供技术学习、探讨和分享; 2. 关于本站的所有留言、评论、转载及引用,纯属内容发起人的个人观点,与本站观点和立场无关; 3. 关于本站的所有言论和文字,纯属内容发起人的个人观点,与本站观点和立场无关; 4. 本站文章均是网友提供,不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属;如您发现该文章侵犯了您的权益,可联系我们第一时间进行删除; 5. 本站为非盈利性的个人网站,所有内容不会用来进行牟利,也不会利用任何形式的广告来间接获益,纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。