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#include<iostream>
#include<vector>
using namespace std;
//trietsigai
int main(){
	int n,x,count=0;
	do{
		cout<<"nhap so phan tu trong danh sach: ";
		cin>>n;cout<<endl;
	} while(n<0);
	vector<int> danh_sach(n);
	for (int i=0;i<n;i++){
		cout<<"Nhap phan tu thu "<<i+1<<": ";
		cin>>danh_sach[i];
	}
	cout<<"Nhap gia tri x: ";
	cin>>x;
	for (int i=0;i<n;i++){
		if (danh_sach[i]==x){
			count++;
		}
	}
	cout<<"so lan xuat hien: "<<count;
	return 0;
}