十进制二进制相互转化C++

#include<iostream>
#include<math.h> 
using namespace std;
#define maxsize 100
int main(){
  int n,arry[maxsize],arry2[maxsize],k,sum=0,t=0;
  cout<<"输入一个数字转化成二进制：\n";
  cin>>n;
  int temp=n;
  for(int i=0;temp!=0;++i){
    arry[i]=temp%2;
    temp=temp/2;
    k=i;
  }
  cout<<n<<"的二进制是：" ; 
  for(int j=k;j>=0;--j){
    cout<<arry[j];
  }
  cout<<"\n二进制转化为十进制，输入一个二进制数\n";
  string s;
  cin>>s;
  int length=s.length();
  for(int i=length-1;i>=0;--i){
    t=pow(2,i);
    int exchange=s[i]-'0';
    sum+=exchange*t;
  }
  cout<<s<<"的十进制为："<<sum;
  return 0;
}