#include <iostream>

using namespace std;

void nhap_mang(float a[], int &n) {
	float x;
	do {
		cout<<"a["<<n<<"] = "; cin>>x;
		if (x != -1 && n < 100) {
			a[n] = x;
			n++;
		}
	} while (x != -1 && n < 100);
	cout<<"Da nhap "<<n<<" phan tu"<<endl;
}

void hien_thi(float a[], int n) {
	cout<<"\nMang a: "<<endl;
	for (int i = 0; i < n; i++) {
		cout<<"\t"<<a[i];
	}
}

void tim_vi_tri(float a[], int n) {
	float x;
	int dem = 0;
	float b[100];
	cout<<"\nNhap x: "; cin>>x;
	for (int i = 0; i < n; i++) {
		if (a[i] == x) {
			b[dem] = i;
			dem++;
		}
	}
	cout<<"\nGia tri "<<x<<" xuat hien "<<dem<<" lan"<<endl;
	cout<<"\nTai cac vi tri: "<<endl;
	for (int i = 0; i < dem; i++) cout<<"\t"<<b[i];
}

int main() {
	int n;
	float a[100];
	nhap_mang(a,n);
	hien_thi(a,n);
	tim_vi_tri(a,n);
	return 0;
}