a=5 1 1,* b = & ampa;
A is an integer variable.
B is an integer pointer variable, pointing to a.
printf("%d\n ",* b);
Is the output pointer variable b,
The output result indicating the value of the variable is 5 1 1.
Or:
* B = & Sentence A is to assign the value of address A to * B.
So the value of printf ("%d\n", *b) is 5 1 1.
Extended data:
And operation is usually used for binary bit extraction operation. For example, the result of a number and 1 is to take the last bit of the binary. This can be used to judge the parity of an integer. The last bit of the binary is 0, which means that the number is even, and the last bit is 1, which means that the number is odd.
Or operation is usually used for unconditional assignment of specific bits of binary. For example, the result of a number or 1 is to forcibly change the last bit of the binary to 1. If you need to change the last bit of the binary to 0, just subtract one from this number or 1. Its practical significance is to forcibly change this number to the nearest even number.
Baidu encyclopedia-bit operation