1.链接地址：

http://poj.org/problem?id=2105

http://bailian.openjudge.cn/practice/2105

2.题目：

IP Address

Time Limit: 1000MS		Memory Limit: 30000K
Total Submissions: 18146		Accepted: 10456

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<=9) 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

4

00000000000000000000000000000000

00000011100000001111111111111111

11001011100001001110010110000000

01010000000100000000000000000001 

Sample Output

0.0.0.0

3.128.255.255

203.132.229.128

80.16.0.1

Source

México and Central America 2004

3.思路：

4.代码：

 #include "stdio.h"

 #include "stdlib.h"

 int f(char input[],int start)

 {

     int ans=;

     int i;

     for(i=;i<;i++)

     {

        ans=ans*+(input[i+start]-'');

     }

     return ans;

 }

 int main()

 {

     int a,b,c,d;

     int n;

     int i;

     char input[];

     scanf("%d\n",&n);

     for(i=;i<n;i++)

     {

         gets(input);

         a=f(input,);

         b=f(input,);

         c=f(input,);

         d=f(input,);

         printf("%d.%d.%d.%d\n",a,b,c,d);

     }

     //system("pause");

     return ;

 }