杭电2031 十进制转换成任意进制

#include<iostream>
#include<string>
#include<vector>
using namespace std;
int main(){
	int n,r,t;
	vector<int>v;
	while(cin>>n>>r){
		v.clear();
		int flag=0;
		if(n<0){
		   n=-n;
		   flag=1;//标识符，以后好还原数值 
		}
		t=n;
		while(t>0){
	   	   v.push_back(t%r);
	   	    t=t/r; 
	   }
	    if(flag)
	    	cout<<'-';    
	   for(int i=v.size()-1;i>=0;i--){
            if (v[i] == 10)
                cout << 'A';
            else if (v[i] == 11)
                cout << 'B';
            else if (v[i] == 12)
                cout << 'C';
            else if (v[i] == 13)
                cout << 'D';
            else if (v[i] == 14)
                cout << 'E';
            else if (v[i] == 15)
                cout << 'F';
            else cout <<v[i];
        }
        cout<<endl;
        }

		

	return 0;
}