进制转换 正进制

#include<bits/stdc++.h>
#define int long long
#define MAX(a,b,c) max(a,max(b,c))
#define MIN(a,b,c) min(a,min(b,c))
#define pb push_back
#define fi first
#define se second
typedef long long ll;
typedef long long LL;
typedef unsigned long long ull;
typedef unsigned long long uLL;
using namespace std;
const int maxn=1e6+10;
map<int,char> mp;
int32_t main()
{
    mp[0]='0';  mp[1]='1'; mp[2]='2'; mp[3]='3'; mp[4]='4';
    mp[5]='5';  mp[6]='6'; mp[7]='7'; mp[8]='8'; mp[9]='9';
    mp[10]='A'; mp[11]='B';mp[12]='C';mp[13]='D';mp[14]='E'; mp[15]='F';
    int n,m; cin>>n>>m;
    int num=fabs(n);
    int k=m;
    stack<char> vs;
    while(num)
    {
        int c=num%k; cout<<c<<endl;
        vs.push(mp[c]);
        num=num/k;
    }
    cout<<n<<"=";
    if(n<0) cout<<"-";
    while(!vs.empty())
    {
        cout<<vs.top(); vs.pop();
    }
}