问题标题: 酷町堂：3815

#include <bits/stdc++.h>

using namespace std;

int a[1005];

unsigned long long erji(int a) {

unsigned long long b=0,c=0;

while(a!=0) {

c++;

b+=pow(10,c)*(a%2)/10;

a/=2;

}

return b;

}

int x[1005];

int main() {

int n,cnt=0;

cin>>n;

for(int i=1;i<=n;i++) {

cin>>a[i];

unsigned long long w=erji(a[i]);

while(w!=0) {

cnt++;

x[cnt]=(w%100);

w/=100;

}

for(int j=cnt;j>=1;j--) {

if(x[j]==0)

cout<<"A";

else if(x[j]==1)

cout<<"B";

else if(x[j]==10)

cout<<"C";

else if(x[j]==11)

cout<<"D";

x[j]=0;

}

cnt=0;

cout<<endl;

}

return 0;

}

这题哪错了？