SHL and SHR

X: = x SHL 1 shifts the binary number to the left by 1 bit, and the end is filled with 1 zero, which is equivalent to X: = x * 2;
X: = x SHL 2 binary number shifts two places to the left, and the end is supplemented with two zeros, which is equivalent to X: = x * 4;
...
X: = x SHL n shifts the binary number to N places left, and the end is supplemented with n zeros, which is equivalent to X: = x * 2 ^ N;

X: = x SHR 1 shifts the binary number to the right by 1 bit. The first part is filled with 1 zero, which is equivalent to X: = x Div 2;
X: = x SHR 2 binary number shifts two places to the right. The first part is supplemented with two zeros, which is equivalent to X: = x Div 4;
...
X: = x SHR n shifts the binary number to N places to the right. The first part is supplemented with n zeros, which is equivalent to X: = x Div (2 ^ N );