poj 2799 IP Networks (模拟/水题)

#include <iostream>
#include <cstring>
#include <algorithm>
#include <cstdio>
using namespace std;

struct node
{
    char k[35];
} data[1005];

bool cmp(node a,node b)
{
    if(strcmp(a.k,b.k)<0) return true;
    else return false;
}

void cut(char *str,int num)
{
    int ans=0;
    int q=8;
    int flag=1;
    for(int i=0; i<strlen(str); i++)
    {
        if(str[i]!=‘.‘)
        {
            ans=ans*10+str[i]-‘0‘;
        }
        else
        {
            flag++;
            while(ans)
            {
                data[num].k[q]=ans%2+‘0‘;
                ans=ans/2;
                q--;
            }
            q=8*flag;
            ans=0;
        }
    }
    while(ans)
    {
        data[num].k[q]=ans%2+‘0‘;
        ans=ans/2;
        q--;
    }
    data[num].k[33]=‘\0‘;
}

int main()
{
    int m;
    char k[35];
    freopen("ip.in","r",stdin);
    freopen("ip.out","w",stdout);
    while(cin>>m)
    {
        for(int i=0; i<m; i++)
        {
            cin>>k;
            memset(data[i].k,‘0‘,sizeof(data[i].k));
            cut(k,i);
            //cout<<data[i].k<<endl;
        }
        sort(data,data+m,cmp);
        int n=0;
        /*for(int i=0;i<m;i++)
        {
            cout<<data[i].k<<endl;
        }*/
        for(int i=1; i<=32; i++)
        {
            if(data[0].k[i]==data[m-1].k[i])
            {
                n++;
            }
            else break;
        }
        for(int i=n+1;i<=32;i++)
        {
            data[m-1].k[i]=‘0‘;
        }
        //cout<<data[m-1].k<<endl;
        int up=128;
        int ans=0;
        for(int i=1;i<=32;i++)
        {
            ans=ans+up*(data[m-1].k[i]-‘0‘);
            up=up/2;
            if(up==0)
            {
                cout<<ans;
                if(i!=32)
                cout<<‘.‘;
                up=128;
                ans=0;
            }
        }
        cout<<endl;
        for(int i=1;i<=n;i++)
        {
            data[m-1].k[i]=‘1‘;
        }
        ans=0;
        for(int i=1;i<=32;i++)
        {
            ans=ans+up*(data[m-1].k[i]-‘0‘);
            up=up/2;
            if(up==0)
            {
                cout<<ans;
                if(i!=32)
                cout<<‘.‘;
                up=128;
                ans=0;
            }
        }
        cout<<endl;
    }
    return 0;
}