#include<iostream>
#include<cstring>
#include<string>
#include<queue>
#include<map>
#include<cstdio>
using namespace std;
template <typename T>
class Sqlist{
public:
T data[100];
int n;
void initData();
void deleteXone(T x);
void deleteXtwo(T x);
void deleteXthree(T x);
void outData();
private:
};
template <typename T>
void Sqlist<T>::outData(){
for(int i=0; i<n; ++i)
cout<<data[i]<<" ";
cout<<endl;
}
template <typename T>
void Sqlist<T>::initData(){
cin>>n;
for(int i=0; i<n; ++i)
cin>>data[i];
}
template <typename T>
void Sqlist<T>::deleteXone(T x){
int k = 0;
for(int i=0; i<n; ++i)
if(data[i] != x)//如果当前元素是 x,那么忽略该元素
data[k++] = data[i];
n = k;
outData();
}
template <typename T>
void Sqlist<T>::deleteXtwo(T x){
int k = 0;//记录空位的数目
for(int i=0; i<n; ++i){
if(data[i]==x)
++k;
else
data[i-k] = data[i];//向前移动k个位置
}
n = n-k;
outData();
}
template <typename T>
void Sqlist<T>::deleteXthree(T x){
int i=0, j=n-1, k=0;
while(i < j) {//不断的将data右边非x的元素 移向 data左边是x的元素的位置
while(data[i]!=x && i<j) ++i;
while(data[j]==x && i<j) --j;
if(i>=j) break;
data[i] = data[j];
++k;
}
n = n-k;
outData();
}
int main() {
Sqlist<int> sq;
sq.initData();
sq.deleteXone(2);
sq.deleteXtwo(0);
sq.deleteXthree(4);
return 0;
}
/*
1 2 0 3 4 6 8 5 9 7
*/