课堂作业

源代码如下：

package classone;
import java.util.Scanner;
public class Test {
        static int number=50;         
        static int[] t1 = new int[number];
        static int[] t2 = new int[number];                //从第几个开始子数组
        static int[] t3 = new int[number];                            //从第几个开始子数组之和
        static int[] t4 = new int[number];                //从第几个开始子数组
        static int[] t5 = new int[number];
        static int[] t6 = new int[number];                //从第几个开始子数组
        static int[] t7 = new int[number];
        static int[] t8 = new int[number];
   
    public static void input() {
        t1[0]=0;t2[0]=0;t3[0]=0;
        System.out.println("输数字数量：");
        Scanner input=new Scanner(System.in);
        number=input.nextInt();
        
        for(int i=1;i<=number;i++)
        {
            
            int a=(int)(Math.random()*2+1);
            int aa=(int)(Math.pow(-1, a));
            System.out.println(aa);
            int aaa=(int)(Math.random()*100+1);
            int b=aa*aaa;
            t1[i]=b;
        }
        System.out.println("T1数组：");
        for(int i=1;i<=number;i++){             
            System.out.print("["+t1[i]+"]"); }
    }                                                      //输入数组
    
    public static void vs() {
        int max=0;//比较
        int b=t1[1];
        int count=0;
        int single;
        int single1;
        int icount=0;
        int jcount=0;
        int sum=0;
        for(int i=1;i<=number;i++) 
        {
            icount++;   //记录I执行次数
            int num=0;   //当前数组之和
            for(int j=i;j<=number;j++) 
            {
                count++;         //计数比较了多少给数组
                jcount++;        //记录J执行次数
                num+=t1[j];    //当前数组之和
                t2[j]=num;    //t2存储当前数组之和 
                t2[0]=t2[1];
                
                
                for(int s=1;s<=number;s++)
                {
                    max=t2[j-1];
                    if(max<t2[j]) 
                    {
                        max=t2[j];
                    }        
                }
                
                
                t3[count]=max;
                
//                System.out.println(t3[count]);
//                t3[0]=t3[1];
                sum=t3[1];
                for(int a=1;a<=count;a++) {
                    if(sum<t3[a]) {
                        sum=t3[a];
                    }
                }
                System.out.println();
                System.out.println("----------------------------");
                System.out.println("当前最大子数组之和为："+sum);
                System.out.println("当前共检查了"+count+"个子数组");
                System.out.println("该子数组是从第"+i+"个到第"+j+"个");
                System.out.println("当前子数组之和为"+t2[j]);
                System.out.println("继续？输入1 回滚？输入2");
                System.out.println("----------------------------");
                Scanner input=new Scanner(System.in);
                single=input.nextInt();
                if(single==2) {
                    System.out.println("输入要回滚的序号：");
                    single1=input.nextInt();
                    if(single1>icount) {
                        count=single1-1;
                        j=single1-icount;
                        num=0;
                        for(int q=i;q<=j;q++)
                        {
                            num+=t1[i];
                        }
                    }else if(single1<icount) {
                        j=1;
                        i=single1;
                        count=single1-1;
                        num=0;
                        for(int q=i;q<=j;q++)
                        {
                            num+=t1[i];
                        }
                    }
                }
        }
    }
        System.out.println("\n"+"子数组之和最大值为："+sum);
    }
    public static void main(String[] args) {
        input();
        vs();
    }
}

结果