java算法专题-归并排序
归并的思想就是分治.时间复杂度..忘记了
大概实现了下..还真挺费劲的...
很受打击啊...还有什么好的排序算法..大家给推荐下我试着弄弄
没怎么写注释..以此作为我的备用.
这几天的思考中我终于发现..理解和会用和精通是两个概念..
学海无涯.人生苦短啊
public class Test1 {public static void main(String[] args) {int[] arr1 = { 4,23,234,3,41,311,3,5 ,56,5,46};int[] arr2 = { 4,23,234,3,41,311,3,5 ,56,5,46};Test1 test1 = new Test1();test1.splitAndMerger(arr1, 0, arr1.length-1);test1.printArray(arr1);test1.printArray(arr2) ;Arrays.sort(arr2) ;test1.printArray(arr2) ;}public void splitAndMerger(int[] ints, int begin, int end) {int mid = (begin + end) / 2;if (end > begin) {splitAndMerger(ints, begin, mid);splitAndMerger(ints, mid + 1, end);merger(ints, begin, mid, end);}}public void merger(int[] ints, int begin, int mid, int end) {int temp1 = 0;int temp2 = 0;int[] arr1 = Arrays.copyOfRange(ints, begin, mid+1);int[] arr2 = Arrays.copyOfRange(ints, mid+1, end+1);for (int i = begin; i <= end; i++) {if (temp1 == arr1.length && temp2 == arr2.length) {break;}if (temp1 == arr1.length) {ints[i] = arr2[temp2];temp2++;continue;}if (temp2 == arr2.length) {ints[i] = arr1[temp1];temp1++;continue;}if (arr1[temp1] > arr2[temp2]) {ints[i] = arr2[temp2];temp2++;} else {ints[i] = arr1[temp1];temp1++;}}}public void printArray(int[] array) {this.printArray(array, 0, array.length-1);}public void printArray(int[] array, int begin, int end) {for (int i = begin; i <= end; i++) {System.out.print(array[i] + "");}System.out.println();}}