Please help me Luogu Beginner Contest #27 G problem, thanks.

Easy Version WA on #6，Hard Version WA on #5,#7,#8,#9.

This is my Code.

#include<bits/stdc++.h>
using namespace std;
inline void rd(int &res){
	char c;res=0;
	while(c=getchar(),c<48);
	do res=(res<<3)+(res<<1)+(c^48);
	while(c=getchar(),c>=48);
}
int n,k;
int a[1000010];
signed main(){
	rd(n),rd(k);
	if (n*9<k){
		printf("1");
		for (int i=1;i<n;i++) printf("0");
		return 0;
	}
	int i=1;
	for (;i<=k/9;i++) a[i]=9;
	k%=9; a[i]=k;
	if (i!=n) a[i]--,a[n]++;
	for (int i=n;i>=1;i--) printf("%d",a[i]);
	return 0;
}