rt，我的代码在自己的机子上是可以跑出正确答案的

但是在洛谷的Linux下却没法跑出正确答案

想知道是哪里出现了问题

以下是我的代码

#include<bits/stdc++.h>
#include<iostream>
#include<iomanip>
#include<cstdio>
#include<stack>
#include<list>
#include<map>
#include<set>
#include<cmath>
#include<cstring>
#include<queue>
#include<algorithm>
#include<vector>
#define ll long long
#define reg register int
#define gc getchar()
#define MAXN 1000001
#define MOD

using namespace std;
inline ll read( void ) ;

int from,to,top;
int num ; 
string s;
int a[MAXN];

int main( void ) {
	
	from = read();
	char ch;
	while(1){
		
		ch = gc;
		if( ch == '\n' ) break;
		num *= from;
		if( ch >= '0' && ch <= '9' ) num += (ch-'0');
		else num += ( ch-'A'+10 );
		
	}
	to = read();
	int top = 0;
	while(1){
		top++;
		a[top] = num % to;
		num /= to;
		if(!num)break;
	}
	for( reg i = top ; i >= 1  ; i-- ){
		
		if( a[i] < 10 ) cout << a[i];
		else cout << char( a[i]-10+'A' );
		
	}

	return 0;
}

inline ll read( void ) {
	ll x = 0 , f = 0 ;
   	char ch = gc ;
   	while( !isdigit( ch ) )
    	f |= ( ch == '-' ) , ch = gc ;
   	while( isdigit( ch ) )
    	x = ( x << 1 ) + ( x << 3 ) + ( ch ^ 48 ) , ch = gc ;
    return f ? -x : x ;
}