Nội dung kiến thức:
	- Toán tử & biểu thức logic
	- Nhập xuất dữ liệu (input/output)
	- Biểu thức điều kiện

Bieu thuc logic: Menh de dieu kien, loop

int x1 = 5;
int x2 = 8;

x1 > x2 => sai: false
x1 < x2 => dung: true
x1 <= x2
	x1 < x2: true
	x1 == x2: false
		-> true || false -> true
x1 >= x2
	-> false

x1 != x2 -> true
x1 == x2 => sai: false

#main.c

#include <stdio.h>
#include <stdlib.h>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */

int main(int argc, char *argv[]) {
	//Slide 3:
	//Khai bao bien so nguyen t1, t2, t3
//	int t1;
//	int t2;
//	int t3;
	int t1, t2, t3;
	
	//Gan du lieu
	t1 = 10;
	t2 = 12;
	t3 = 100;
	
	//Khai bao bien k1 = 10, k2 = 20, k3 = 15;
	int k1 = 10, k2 = 20, k3 = 15;
	//Khai bao bien x1, x2, x3 co cung gia tri 12;
	int x1, x2, x3;
	x1 = x2 = x3 = 12;
	printf("x1 = %d", x1);
	
	//Phep tinh +, -, *, /, % (mode: chia lay du)
	x1 = 10;
	x2 = 5;
	
	x3 = x1 + x2;//15
	x3 = x1 - x2;//5
	x3 = x1 / x2;//2
	x3 = x1 * x2;//50
	x3 = x1 % x2;//0
	x2 = x2 % x1;//5
	
	//Cach viet tat
	x1 = x1 + x2;//x1 = 15, x2 = 5
	x1 += x2; //cach viet tat -> ghi nho
	
	x1 = x1 - x2;
	x1 -= x2;
	
	x1 = x1 / x2;
	x1 /= x2;
	
	x1 = x1 * x2;
	x1 *= x2;
	
	x1 = x1 % x2;
	x1 %= x2;
	
	//TH dac biet -> chi thay doi 1 gia tri -> +, -
	x1 = 2;
	x2 = 3;
	
	x1 = x1 + 1;
	x1 += 1;
	//cong cong sau -> gan gia tri trc -> sau do moi day doi gia tri
	x1++;//thay doi gia tri cua x1 len 1 don vi
	//cong cong truoc -> thay doi gia tri x1 -> sau do moi gan gia tri moi cua x1
	++x1;//Thay doi gia tri cua x1 len 1 don vi
	
	x1 = x1 - 1;
	x1 -= 1;
	x1--;
	--x1;
	
	//Vi du
	x1 = 5;
	x2 = x1++;
	printf("\nx2 = %d", x2);//x1 = 6, x2 = 5;
	x2 = ++x1;//x2 = 7, x1 = 7
	printf("\nx2 = %d, x1 = %d", x2, x1);
	
	x1 = 3;
	x2 = ++x1;
	//x1 = 4, x2 = 4
	x3 = x1++ + ++x1 - --x2 + 2;
	//x3 = 4(x1=5) + (x1=6) 6 - (x2=3) 3 + 2 = 9
	printf("\nx1 = %d, x2 = %d, x3 = %d", x1, x2, x3);
	//x1=6, x2=3, x3=9
	
	//khai bao 1 ky
	char c = 'A';
	printf("\nc = %c", c);
	
	//khai bao chuoi (string) - text: "ABC"
	//khai bao str co do dai toi da la 30 ky tu
	char str[30] = "Sinh vien 456Aptech";
	
	//s1: String -> do dai toi da la 3 ky tu
	char s1[3] = "22"; //error -> vuot qua so ky tu cho phep
	
	printf("\nstr = %s", str);
	
	//Nhap du lieu
//	int m1, m2;
//	m1 = 10;
//	m2 = 12;
	//cong 2 so nguyen
	printf("\n================= nhap tu ban phim =================\n");
	int a, b, tong;
	//nhap gia tri tu ban phim cho bien a
	//su dung ham scanf -> so nguyen: %d (so thuc: %f, ky tu: %c, string: %s)
	//					-> bien su dung: &a -> ghi nho
	printf("\nNhap gia tri a = ");
	scanf("%d", &a);
	printf("\na = %d", a);
	printf("\nNhap gia tri b = ");
	scanf("%d", &b);
	
	tong = a + b;
	printf("\nTong: %d", tong);
	//Tim loi sai trong code sau
	//Loi lap trinh
	printf("\nNhap b = ");
	scanf("%d", &b);
	printf("\nNhap a = ");
	scanf("%d", &a);
	
	tong = a + b;
	printf("\nTong: %d", tong);
	
	
	printf("\nIn dau nhay kep: \"");
	
	fflush(stdin);fflush(stdout);//getchar();
	char kk;
	printf("\nNhap ky tu kk = ");
//	scanf("%c", &kk);
	kk = getchar();
//	printf("\n%c", kk);
	putchar(kk);
	
	return 0;
}