Zuosige always has bad luck. Recently, he is in hospital because of pneumonia. While he is taking his injection, he feels extremely bored. However, clever Zuosige comes up with a new game.
Zuosige writes two binary number on a paper, which are labelled as A and B. It is guaranteed that A is greater than B and A xor B = 2n+1-1 (n is the length of A), where xor means bitwise exclusive-or. Now he wants to know the value of A - B in binary.
The first line contains one integer T, indicating the number of test cases.
In one test case, there are two lines.
In the first line, there are two integers n, m (0<=m < n/2, 1<=n<=1000000), indicating the length of the numbers and the number of 1s in B.
In the second line, there m integers indicating the positions where B is 1. Positions starting from 1, which is the lowest bit. It is guaranteed that A is greater than B.
For each test case, output a line indicating the answer in binary without leading zero.
2
9 3
2 5 6
8 5
1 2 3 5 6
110011011
10010001
#include <iostream>
#include <stdio.h>
#include <string.h>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <vector>
#include <math.h>
#include <algorithm>
using namespace std;
#define ls 2*i
#define rs 2*i+1
#define up(i,x,y) for(i=x;i<=y;i++)
#define down(i,x,y) for(i=x;i>=y;i--)
#define mem(a,x) memset(a,x,sizeof(a))
#define w(a) while(a)
#define LL long long
const double pi = acos(-1.0);
#define N 1000005
#define mod 19999997
const int INF = 0x3f3f3f3f;
#define exp 1e-8
int a[N],b[N],ans[N];
int main()
{
int t,n,m,i,j,k;
cin >> t;
w(t--)
{
cin>>n>>m;
up(i,0,n)
{
b[i] = 0;
a[i] = 1;
}
w(m--)
{
scanf("%d",&k);
b[k] = 1;
a[k] = 0;
}
int flag = 1;
down(i,n-1,0)
{
if(a[i]==0&&flag) continue;
printf("%d",a[i]);
flag = 0;
}
printf("\n");
}
return 0;
}
原文：http://blog.csdn.net/libin56842/article/details/45624073