pku acm 1023

#include <iostream>
#include <cstdio>
#include <string>
#include <limits>
#include <cmath>
#include <algorithm>
using namespace std;

class Funk
{
public:
typedef long long LL;
typedef unsigned long long ULL;

private:
int nbits;//位数
string sbits;//每一位的正负情况
ULL max,min;
bool flg;//标记最小数的符号

void initmaxmin()
{
//cout<<"sbits.size = "<<sbits.size()<<endl;
max = 0,min = 0;
flg = false;
for(int i = nbits-1; i >= 0; i--)
{
if(sbits[i] == 'p')
{
max += (ULL)(pow(2.0,nbits-i-1));
}
else //sbits[i] == 'n'
{
flg = true;
min += (ULL)(pow(2.0,nbits-i-1));
}
//cout<<"i = "<<i<<" "<<decToBin(min)<<endl;
}
if(flg == false)min = 0;
}
public:
Funk(string s):sbits(s)
{
nbits = sbits.size();
initmaxmin();
}
Funk(int n,string s):nbits(n),sbits(s)
{
initmaxmin();
}

//10进制数到2进制数的转换
string decToBin(ULL n)// n >= 0
{
if(n == 0)return "0";
if(n == 1)return "1";
string s;
while(n > 1)
{
if(n%2 == 0)
s.push_back('0');
if(n%2 == 1)
s.push_back('1');
n /= 2;
}
s.push_back('1');
reverse(s.begin(),s.end());
return s;
}

string representation(LL N)
{
if(N < 0)
{
if(flg == false)return "Impossible";
if(N*(-1) > min)return "Impossible";
}
if(N > 0 && N > max)
return "Impossible";

ULL tmp = N + min;
string s = decToBin(tmp);
if(s.size() < nbits)
{
string t(nbits-s.size(),'0');
t += s;
s = t;
}
//cout<<"s.size = "<<s.size()<<endl;
for(int i = 0; i < nbits; i++)
{
if(sbits[i] == 'n')
{
s[i] = (s[i] == '0')?'1':'0';
}
}
return s;
}
};

int main()
{
freopen("in.txt","r",stdin);
/*freopen("out.txt","w",stdout);*/
/*cout<<numeric_limits<long long>::min()<<endl;
cout<<numeric_limits<long long>::max()<<endl;
cout<<numeric_limits<unsigned long long>::max()<<endl;*/

int t;      // 1 <= t <= 10
int k;      // 1 <= k <= 64
string s;
Funk::LL N; //-2^63 ≤ N < 2^63

cin>>t;
while(t--)
{
cin>>k>>s>>N;
Funk f(k,s);
cout<<f.representation(N)<<endl;
}
return 1;
}

测试数据：

6

64

nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn

-9223372036854775808

1

n

2

5

ppppp

0

5

nnnnn

-32

5

nnnnn

-31

5

nnnnn

1

5

nnnnn

0

3

pnp

6

4

ppnn

10

结果如下：

1000000000000000000000000000000000000000000000000000000000000000

Impossible

00000

Impossible

11111

Impossible