2.25号课堂测试

对一维数组随机一段求和求最大

package shuzi;
import java.util.Scanner;

public class Suzi {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
          System.out.println("请输入输入数字的个数");
          Scanner sc = new Scanner(System.in);
          int n,i;
          n=sc.nextInt();
          System.out.println("请输入输入"+n+"数字");
          int[] a = new int[n];
          for(i=0;i<n;i++)
          {
              a[i]=sc.nextInt();
              
          }
          for(i=1;i<n;i++)
            {
                if(a[i]+a[i-1]>a[i])
                    a[i]=a[i]+a[i-1];
            }
          int ans=-100000;
            for(i=0;i<n;i++)
            {
                if(ans<a[i])
                {
                    ans=a[i];
                }
            }
        
            System.out.println("最大的数为"+ans);
    
    }

}

对循环的一维数组进行求和，每个值只用一次

package shuzi;

import java.util.Scanner;

public class Suzi
{
    public static void main(String args[]) {
        Scanner scan=new Scanner(System.in);
        System.out.println("请输入个数");
        int n=scan.nextInt();
        int [] a=new int [n];
        int [] b=new int [n];
        int i,j = 0,k = 0;
        System.out.println("请输入数字");
        for(i=0;i<n;i++) 
        {
            a[i]=scan.nextInt();
            b[i]=a[i];
        }            
        for(i=1;i<n;i++)
        {
            if(a[i]+a[i-1]>a[i])
            {
                a[i]=a[i]+a[i-1];
                j=i;
            }else {
                k=i;
            }
        }
        for(i=j+1;i<n;i++) {
            a[i]=a[i]+a[i-1];
        }
        for(i=0;i<k;i++) {
            if(a[n-1]+b[i]>a[n-1]) {
                a[n-1]=a[n-1]+b[i];
            }
        }
        int ans=-100000;
        for(i=0;i<n;i++) {
            if(ans<a[i]) {
                ans=a[i];
            }
        }
        System.out.println(ans);
    }
}