1590 - IP Networks

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cmath>
#include<cctype>
#include<vector>
#include<queue>
#include<map>
#include<set>
#define eps 10e-6

using namespace std;

typedef long long ll;

int ip[1005][35];

void solve(int t,int *sum,int id)
{
int tmp[10],p = 0,w = t;
while(t>0)
{
tmp[p++] = t%2;
t/=2;
}
while(p<8) tmp[p++] = 0;
for(int i=7;i>=0;i--)
ip[id][(*sum)++] = tmp[i];
}

int cal(int st,int len)
{
int ret = 0;
for(int i=st;i<st+8;i++)
{
if(i<len) ret = ret*2+ip[0][i];
else ret = ret*2;
}
return ret;
}
int calb(int st,int len)
{
int ret = 0;
for(int i=st;i<st+8;i++)
{
if(i<len) ret = ret*2+1;
else ret = ret*2;
}
return ret;
}

int main()
{
int n;
while(~scanf("%d",&n))
{
int x[4];
for(int i=0;i<n;i++)
{
scanf("%d.%d.%d.%d",&x[0],&x[1],&x[2],&x[3]);
int cnt = 0;
for(int j=0;j<4;j++)
solve(x[j],&cnt,i);
}
int len = 32;
for(int i=1;i<n;i++)
{
int s = 0;
for(int j=0;j<32;j++)
{
if(ip[i][j]==ip[0][j])
s++;
else break;
}
len = min(len,s);
}
for(int i=0;i<24;i+=8)
printf("%d.",cal(i,len));
printf("%d\n",cal(24,len));
for(int i=0;i<24;i+=8)
printf("%d.",calb(i,len));
printf("%d\n",calb(24,len));
}
return 0;
}