从键盘输入两个常数，求其最大公约数，并以常数形式输出-the greatest common divsion

1) it is code which gives lcm and gcd of 2 numbers. 2) to check if a number satisfies 2 out of 5 condition. 3) to check if the number is odd or even. 4) to square a given number. 5) to find number of 0s and 1s in a given binary number.