显示代码纯文本
#include<cstdio>
#define N 105
using namespace std;
int t,n,m,k,a[N];
int read(){
int sum=0;bool f=0;char c=getchar();
for(;c<48||c>57;c=getchar())if(c==45)f=1;
for(;c>=48&&c<=57;c=getchar())sum=sum*10+(c&15);
return f?-sum:sum;
}
int main(){
freopen("Sequence.in","r",stdin);freopen("Sequence.out","w",stdout);
t=read();
while(t--)
{
m=read(),k=read();n=0;
for(int i=1;i<=k;i<<=1)
if(k&i)
m-=a[++n]=(1<<i)-1;
if(m<0){printf("-1\n");continue;}
if(m==1)
if(a[1]^1){printf("-1\n");continue;}
else a[1]=2,m--;
if(!m)
{
printf("%d\n",n);
for(int i=1;i<=n;i++)
printf("%d ",a[i]);
printf("\n");
continue;
}
k=0;
for(int i=1;i<=m;i<<=1)
if(m&i)
a[++n]=i,k++;
if(k&1)a[n]=a[n+1]=a[n]>>1,n++;
printf("%d\n",n);
for(int i=1;i<=n;i++){printf("%d ",a[i]);}
printf("\n");
}
return 0;
}