2012年北京邮电大学计算机考研机试试题及答案

package oj_2012_jsj;

import java.util.Scanner;

public class oj_2012_1 {
	public static void main(String[]args){
		Scanner in = new Scanner(System.in);
		int T = in.nextInt();
		while(T>0)
		{
			int n = in.nextInt();
			if(n==0)
				{
					System.out.println();
					continue;
				}
			int num = 1;
			int index = 0;
			while(num<=n)
			{
				num*=2;
				index++;
			}
			num = num/2;
			n-=num;
			/*
			 * 23 10111 5
			 * k[4] = 1;
			 * index = 4; num = 8; n = 7; k[3]=0;
			 * index = 3; num = 4; n = 7; k[2]=1;
			 * index = 2; num = 2; n = 3; k[1]=1;
			 * index = 1; num = 1; n = 1; k[0]=1; 
			 * 
			 */
			int[] k = new int[index];
			int r = index;
			//System.out.println("num: "+num+" index: "+index);
			k[--index] = 1;
			while(n>0){
			num = num/2;
			if(n>=num){
				k[--index] = 1;
				n = n-num;
			}else{
				k[--index] = 0;
			}
			//System.out.println("n: "+n+" index: "+index);
			}
			for(int i=r-1;i>=0;i--){
				System.out.print(k[i]);
			}
			System.out.println();
			T--;
		}
	}
}

package oj_2012_jsj;

import java.util.Scanner;

public class oj_2012_2 {
	public static void main(String[]args){
		
		Scanner in = new Scanner(System.in);
		int T = in.nextInt();
		while(T!=0){
			
			int n = in.nextInt();
			int k = in.nextInt();
			
			int [][]a = new int[n][n];
			int [][]b = new int[n][n];
			int [][]c = new int[n][n];
			
			for(int i=0;i

#include
using namespace std;

typedef struct Bnode{
    int data;
    struct Bnode *lchild,*rchild;
}Bnode,*Btree;

Btree Create_BST(Btree T,int key)
{
    if(T==NULL)
    {
        //cout<<"建立"<data = key;
        T->lchild = NULL;
        T->rchild = NULL;
        return T;
    }
    else
    {
        if(T->data>key)
            {
                //cout<<"T->data: "<data<<" key: "<lchild==NULL)
                {
                    cout<data<lchild = Create_BST(T->lchild,key);
            }
        else
            {
                //cout<<"T->data: "<data<<" key: "<rchild==NULL)
                {
                    cout<data<rchild = Create_BST(T->rchild,key);
            }
            return T;
    }

}

int main()
{
    int n;
    Btree T = NULL;
    cin>>n;
    if(n>=1){
        cout<<"-1"<>key;

        T = Create_BST(T,key);
    }
    return 0;
}

#include
using namespace std;
/*
样例输入：
2
45 00 00 34 7a 67 40 00 40 06 63 5a 0a cd 0a f4 7d 38 ca 09 cd f6 00 50 b4 d7 ae 1c 9b cf f2 40 80 10 ff 3d fd d0 00 00 01 01 08 0a 32 53 7d fb 5e 49 4e c8
45 00 00 c6 56 5a 40 00 34 06 e0 45 cb d0 2e 01 0a cd 0a f4 00 50 ce 61 e1 e9 b9 ee 47 c7 37 34 80 18 00 b5 81 8f 00 00 01 01 08 0a 88 24 fa c6 32 63 cd 8d

样例输出：
Case #1
//第四个是总长度
Total length = 52 bytes  52的二进制：32+16+4     00110100 34
//13\14\15\16是源地址
Source = 10.205.10.244   0A.CD.0A.F4
//17\18\19\20
Destination = 125.56.202.9  7d 38 ca 09
// cd f6 21\22
Source Port = 52726
//23\24
Destination Port = 80



Case #2
Total length = 198 bytes   160+16+16=192+6=198  16*12+6 c6
Source = 203.208.46.1
Destination = 10.205.10.244
Source Port = 80
Destination Port = 52833
*/
int swich(int n,char s)
{
    if(s-'0'>=49)
    {
        int a=s-'0'-49;
        if(n==2)
            return (10+a)*16;
        if(n==1)
            return 10+a;
    }
    else
    {
        if(n==1)
            return  s-'0';
        if(n==2)
            return (s-'0')*16;
    }
}

int swich2(int n,char s)
{
    if(n==1)
    {
        if(s-'0'>=49)
        {
            return s-'0'-49+10;
        }
        else
        {
            return s-'0';
        }
    }
    if(n==2)
    {
        if(s-'0'>=49)
        {
            return (s-'0'-49+10)*16;
        }
        else
        {
            return (s-'0')*16;
        }
    }
    if(n==3)
    {
        if(s-'0'>=49)
        {
            return (s-'0'-49+10)*16*16;
        }
        else
        {
            return (s-'0')*16*16;
        }
    }
    if(n==4)
    {
        if(s-'0'>=49)
        {
            return (s-'0'-49+10)*16*16*16;
        }
        else
        {
            return (s-'0')*16*16*16;
        }
    }
}
    int main()
    {
        int T;
        scanf("%d",&T);
        int num=0;
        while(T--)
        {
            num++;
            string s;
            //第一次输入把空行符读入，其他的不用读
            if(num==1)
                cin.get();
            getline(cin,s);
            //Case #1
            printf("Case #%d\n",num);
            //Total length = 52 bytes
            int Total_length = swich(2,s[9])+swich(1,s[10]);
            cout<<"Total length = "<