Thuc_Hanh

// Thuc_Hanh_2.cpp
#include <iostream>
#include <math.h>

using namespace std;

void BaiToan1() {
	int n, gt;
	do {
		cout<<"Nhap n: "; cin>>n;
	} while (n < 0);
	gt = 1;
	for (int i = 1; i <= n; i++) {
		gt = gt * i;
	}
	cout<<n<<"! = "<<gt;
}

void BaiToan2() {
	int n;
	float f = 0;
	cout<<"Nhap n: "; cin>>n;
	if (n % 2 == 0) {
		for (int i = 0; i <= n; i++) {
			f += (float)1/pow(2, i);
		}
	} else {
		f = sqrt(pow(n, 2) + 1);
	}
	cout<<"F = "<<f;
}

void BaiToan3() {
	int n;
	float x;
	float s = 0;
	cout<<"Nhap x: "; cin>>x;
	do {
		cout<<"Nhap n: "; cin>>n;
	} while (n < 0);
	if (n % 2 == 0) {
		for (int i = 1; i <= n; i++) {
			s += pow(x, i)/pow(3, i - 1);
		}
	}
	cout<<"S = "<<s;
}

void BaiToan4() {
	int n, kq = 0;
	do {
		cout<<"Nhap n: "; cin>>n;
	} while (n < 0);
	while (n > 0) {
		kq = kq * 10 + n % 10;
		n = n / 10;
	}
	cout<<"Ket qua: "<<kq;
}

void BaiToan5() {
	int n;
	bool nguyento;
	cout<<"Nhap n: "; cin>>n;
	for (int i = 2; i < n; i++) {
		nguyento = true;
		for (int j = 2; j <= round(sqrt(i)); j++) {
			if (i % j == 0) {
				nguyento = false;
				break;
			}
		}
		if (nguyento) cout<<i<<" ";
	}
}

void BaiToan6() {
	int n, x;
	cout<<"Nhap n: "; cin>>n;
	x = (int)sqrt(n);
	if (pow(x, 2) == n) {
		cout<<n<<" la so chinh phuong";
	} else {
		cout<<n<<" khong phai so chinh phuong";
	}
}

int main() {
	int luachon;
	cout<<"\tMENU LUA CHON"<<endl;
	cout<<"- Bam phim 1 de lua chon giai bai toan 1"<<endl;
	cout<<"- Bam phim 2 de lua chon giai bai toan 2"<<endl;
	cout<<"- Bam phim 3 de lua chon giai bai toan 3"<<endl;
	cout<<"- Bam phim 4 de lua chon giai bai toan 4"<<endl;
	cout<<"- Bam phim 5 de lua chon giai bai toan 5"<<endl;
	cout<<"- Bam phim 6 de lua chon giai bai toan 6"<<endl;
	cout<<"- Bam phim 0 de lua chon dong ung dung"<<endl;
	cout<<"Nhap lua chon cua ban: "; cin>>luachon;
	switch (luachon) {
		case 1: BaiToan1(); break;
		case 2: BaiToan2(); break;
		case 3: BaiToan3(); break;
		case 4: BaiToan4(); break;
		case 5: BaiToan5(); break;
		case 6: BaiToan6(); break;
		case 0: exit(0);
		default: cout<<"Lua chon khong dung";
	}
	return 0;
}