zcmu-1426: IP Address(水题)

最新推荐文章于 2025-12-21 00:03:36 发布

原创最新推荐文章于 2025-12-21 00:03:36 发布 · 171 阅读

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该代码实现读取输入的二进制流，并将每个32位的二进制序列转换为IPv4的点分十进制格式。程序通过分组每8位并将其转换为十进制数，然后用点号连接各部分，生成合法的IP地址。

Description

Suppose you are reading byte streams from any device, representing IP addresses. Your task is to convert a 32 characters long sequence of '1s' and '0s' (bits) to a dotted decimal format. A dotted decimal format for an IP address is form by grouping 8 bits at a time and converting the binary representation to decimal representation. Any 8 bits is a valid part of an IP address. To convert binary numbers to decimal numbers remember that both are positional numerical systems, where the first 8 positions of the binary systems are:

2^7	2^6	2^5	2^4	2^3	2^2	2^1	2^0
128	64	32	16	8	4	2	1

Input

The input will have a number N (1 <= N <= 100) in its first line representing the number of streams to convert. N lines will follow.

Output

The output must have N lines with a doted decimal IP address. A dotted decimal IP address is formed by grouping 8 bit at the time and converting the binary representation to decimal representation.

Sample Input

00000000000000000000000000000000

00000011100000001111111111111111

11001011100001001110010110000000

01010000000100000000000000000001

Sample Output

0.0.0.0

3.128.255.255

203.132.229.128

80.16.0.1

tip:题目大概意思就是给你一个数n，接下来会有n行只含0和1的一串4个8位二进制数，需要你转化为十进制并以“数字.数字.数字.数字”的格式输出。

代码：

#include <cstdio>
#include <cmath>
#include <iostream>
#include <algorithm>
using namespace std;
typedef long long ll;
 
int main()
{
    int n;
    while(~scanf("%d",&n))
    {
        for(int t=0;t<n;t++)
        {
            string s;
            cin>>s;
            for(int i=0;i<4;i++)
            {
                int sum=0;
                for(int j=0;j<8;j++)
                {
                    if(s[i*8+j]=='1') sum+=pow(2,7-j);
                }
                if(i==0) cout<<sum;
                else cout<<"."<<sum;
            }
            cout<<"\n";
        }
             
    }
    return 0;
}