郑州大学软件技术学院算法分析与设计考试

算法设计与分析

第二单元测试题

目录

算法设计与分析 (1)

第二单元测试题 (1)

目录 (1)

AckerMan (1)

InterDivision (2)

BinarySearch (3)

QuickSort (4)

Perm (5)

MergeSort (6)

AckerMan

import java.util.Scanner;

public class AckerMan {

public static int ac (int n, int m) {

if (n == 0) {

return 1;

} else if (m == 0) {

if (n == 1) {

return 2;

} else if (n >= 2) {

return (n + 2);

}

} else if ((m >= 1) && (n >= 1)) {

return ac(ac(n-1,m),m-1);

}

return 0;

}

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

System.out.println("请输入一个整数n：");

int n = sc.nextInt();

System.out.println("请输入一个整数m：");

int m = sc.nextInt();

System.out.println("结果输出为：" + "\n" + ac(n,m));

}

}

InterDivision

import java.util.Scanner;

public class InterDivision {

public static int q (int n,int m) {

if ((n ==1) || (m ==1)) {

return 1;

}

if (n < m) {

return q(n,n);

}

if (n == m) {

return q(n,m-1)+1;

}

if ((n > m) && (m > 1)) {

return q(n,m-1)+q(n-m,m);

}

return 0;

}

public static void main (String[] args) {

Scanner sc = new Scanner(System.in);

System.out.println("请输入一个整数n:");

int n = sc.nextInt();

System.out.println("请输入一个整数m:");

int m = sc.nextInt();

System.out.println("整数划分结果为：" + "\n" + q(n,m));

}

}

BinarySearch

import java.util.Scanner;

public class BinarySearch{

public static int q(int a[],int x,int left,int right){

if(left>right)return -1;

int mid=(left+right)/2;

if(x==a[mid])return mid;

if(x

else return q(a,x,mid+1,right);

}

public static void main(String [] args){

System.out.println("请输入数组元素个数：");

Scanner sc=new Scanner(System.in);

int s=sc.nextInt();

int a[]=new int[s];

System.out.println("请输入数组元素：");

for(int i=0;i

a[i]=sc.nextInt();

}

System.out.println("请输入要查的元素：");

int x=sc.nextInt();

int left = 0;

int hight = s-1;

System.out.println("您要查找的元素在该数组中的下标为："+ "\n" +q(a,x,left,hight));

}

}

QuickSort

import java.util.Scanner;

public class QuickSort {

public static void quickSort (int a[], int left, int right) { if (left < right) {

int i = left;

int j = right;

int k = a[i];

while (i != j) {

while ((i < j) && (k <= a[j])) {

j--;

}

if (i < j) {

a[i++] = a[j];

}

while ((i < j) && (a[i] <= k)) {

i++;

}

if (i < j) {

a[j--] = a[i];

}

}

a[i] = k;

quickSort(a,left,j-1);

quickSort(a,i+1,right);

}

}

public static void main (String[] args) {

System.out.println("请输入数组的长度：");

Scanner sc = new Scanner(System.in);

int b = sc.nextInt();

int a[] = new int[b];

System.out.println("请输入数组元素：");

for (int i = 0; i < a.length; i++) {

a[i] = sc.nextInt();

}

quickSort(a,0,a.length-1);

System.out.println("快速排序后的结果为：");

for (int i = 0; i < a.length; i++) {

System.out.print(a[i] + " ");

}

}

}

Perm

import java.util.Scanner;

public class Perm {

public void perm (Object list[], int k, int m) { if (k == m) {

for (int j = 0; j <= m; j++) {

System.out.print(list[j] + " ");

}

System.out.print(" ");

} else {

for ( int i = k; i <= m; i++) {

swap(list,k,i);

perm(list,k+1,m);

swap(list,k,i);

}

}

}

private void swap(Object list[], int k, int m) { Object t;

t = list[k];

list[k] = list[m];

list[m] = t;

}

public static void main (String[] args) {

Perm p = new Perm();

System.out.println("请输入数组长度：");

Scanner sc = new Scanner(System.in);

int a = sc.nextInt();

Object list[] = new Object[a];

System.out.println("请输入数组元素：");

for (int i = 0; i < a; i++) {

list[i] = sc.next();

}

System.out.println("全排列输出为：");

p.perm(list, 0, a-1);

}

}

MergeSort

import java.util.Scanner;

public class MergeSort{

int b[]=new int[100];

public void mergeSort(int a[],int left,int right){ if(left

int i=(left+right)/2;

mergeSort(a,left,i);

mergeSort(a,i+1,right);

merge(a,b,left,i,right);

copy(a,b,left,right);

}

}

public void copy(int a[],int b[],int m,int n){ for(int i=m;i<=n;i++){

a[i]=b[i];

}

}

public void merge(int c[],int d[],int l,int m,int r){ int i=l;

int j=m+1;

int k=l;

while((i<=m)&&(j<=r))

if(c[i]<=c[j]){

d[k++]=c[i++];

} else {

d[k++]=c[j++];

}

if(i>m){

for(int q=j;q<=r;q++){

d[k++]=c[q];

}

} else {

for(int q=i;q<=m;q++){

d[k++]=c[q];

}

}

}

public static void main(String[] args){

MergeSort p=new MergeSort ();

System.out.println("请输入数组长度：");

Scanner sc=new Scanner(System.in);

int s=sc.nextInt();

int a[]=new int[s];

System.out.println("请输入数组中的元素：");

for(int i=0;i

a[i]=sc.nextInt();

}

p.mergeSort(a, 0, a.length-1);

System.out.println("合并排序后的数组为：");

for(int i=0;i

System.out.print(a[i]+" ");

}

}