c On the use and practical significance of flag

The for-j loop scans a part of the array once, and swaps it before each large number, so that the last number of the part is the maximum value of the part.

The for-i loop keeps narrowing this range so that the array is the largest, second-maximum, and third-largest from back to front. Minimum.

In the for-j loop, if there is no large number before the decimal, that is, there is a small to large order, and there is no need to continue the loop, the flag will be set to 1, and the for-i loop will jump out after the for-j is executed, and the subfunction will end.

The flag here is mainly used to improve efficiency and does not affect the result.

A good programmer doesn't just look at results, it's also about efficiency!

Test your program with a few more sets of data! You'll find out what's inside!

This data can be stored in a file or generated randomly.

Flag represents a variable in C programming.

A flag is originally a programming instruction that is often used in computer languages, such as C or D, to record a parameter of a variable.

Flags have only two values, 1 (up) and 0 (down), and are usually stored in a fixed area of memory. The program changes the value of the flag at the same time as a certain state change, and learns the state through the flag in other operations, and decides the next action. In other words, flags can be used to help programs make judgments about complex conditions.

Example of a programint a；

flag：a = 1；

cout a = 2；

cout "Program Execution Result: Infinite Loop Output 1

For the above content, please refer to Encyclopedia—flag

Everyone should have heard of C language, in fact, C language is a process-oriented, abstract general programming language, widely used in low-level development, do you know the use of C language flag? The following is the usage of C language flag that I bring to you What does C language flag mean, for your reference, let's take a look!

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Meaning of C language flag C generally sets a variable flag, which is a variable to represent judgment, which is used as a flag. For example, in the case of all the time, the flag is set to 1, and in the other case, the flag is set to 2. The variable is called flag, which is just a matter of habit, and it can also be called something else.

For example, you can set flags, such as event A and event B.

event a is happening flag=1, event a is not happening flag=0;

b detects flag, if flag=1, it means that a is executing, and b is not executing.

b detects the flag, if flag=0, it means that a is not executed, and b executes.

It is often used to access shared memory at the same time, or to use the same variable, mutually exclusive!

Example 1 of the use of C flag includes

#define n 5

void swap(int arr,int a, int b);/

bool flag;

Bubbling sorting. for (int i = 0; i < n - 1; i++)

Flag is often used as the name of a variable that indicates a change. In the C language, pants intellectuals generally set a variable flag, which is a variable to represent judgment, which is used as a flag. Slamming.

flag is not a keyword in C, it is usually used as the name of a variable to indicate a change, and a variable flag is generally set in C, which is a variable to represent a judgment, as a flag.

For example, in one case, the flag is set to 1, and in the other case, the flag is set to 2. The variable is called flag, which is just a matter of habit, and it can also be called something else.

Example: Set flags, such as event A and event B.

event a is happening flag=1, event a is not happening flag=0;

b detects flag, if flag=1, it means that a is executing, b does not execute b detects flag, if flag=0, it means that a is not executed, b is executed is often used to access shared memory at the same time, or the same variable, mutually exclusive.

There is no special meaning, it is not a reserved word, it can be defined as anything arbitrary, variables, constants, class name structs, all arbitrary.

It is a self-defined variable that is generally used as a sign of a state. For example, if a program wants to do different things depending on the parity of integers, you can use an int flag; to represent the parity of integers. flag=1 can represent odd numbers, and flag=0 can represent even numbers.

flag is a flag, many library function parameters have flags, in fact, some specific integers, these numbers into binary only one bit is 1, the rest of the bits are zero, so it is easy to use bit operations to merge into a number or detect which flags a number is combined. It can be achieved with a single parameter that passes a lot of information.

C language does not have the keyword flag, it should be a variable you define yourself, we generally set a variable flag in c, which is a variable to represent judgment, as a flag. For example, when it is always the case, the flag is set to 1, and in the other case, the flag is set to 0, and the variable name is flag, which is just a matter of habit, and can also be called something else.

In recent years, the development speed of the domestic network is still very fast, you can understand a lot of things through the Internet, so there are many hot words on the Internet have become popular, among which flag is a very popular word, what does the old flag mean on the Internet? What kind of meme is to set up a flag? There may be some friends who don't know very well, on the Internet, many netizens will set up the word flag in the word flag, especially in some TV series and anime barrages, the word flag is very common.

Let's briefly introduce what the old flag on the Internet means.

In fact, the Chinese meaning of the word flag is the meaning of "flag", and it is also a word often used in programming, which mainly refers to the basis for judging a certain thing in programming. That is to say, the flag refers to the key content that determines the outcome of a thing, and it is a more directly related thing to the ending, and the flag is the meaning of triggering the key thing.

Later, the word flag often appeared in many anime, and began to slowly develop into an Internet term, which generally means an ominous signal on the Internet. For example, if you say something very firm or make a very firm decision, but the final result is often the opposite, which can also be understood as the meaning of a crow's mouth.

The stalk of flag is also a language that many people often use nowadays, and it is also a development of the word flag. To explain it simply, it is actually a person who says something or does something, but the end result is that he is slapped in the face by what he does. Then the opposite key words or key things done before the ending are called flags, which are actually the completely opposite foreshadowing for the ending.

Let's give some examples to illustrate the common methods of flag in TV dramas, such as calling his girlfriend before the war and saying that he would marry her when he returns after the war, then most of the ending of this person is death. For example, if you stand where you are before I come back, you must not walk around, and generally those who stay behind will walk around, and these words are called flags. Now the use of flag still has several meanings, such as the meaning of foreshadowing, indicating that some foreshadowing in the plot allows people to guess the future development.

There is also the meaning of the crow's mouth, which is generally an act that echoes the opposite bad outcome, and is also known as the death flag and the failure flag. There is also a meaning of setting one's own goals, and others think that they will fail.

The above is a brief introduction to what the old saying of flag on the Internet means, the meaning of the word flag on the Internet is actually relatively diverse, but the more commonly used is similar to the meaning of a crow's mouth, or what you have said and done is completely different from the result, and you are slapped in the face by yourself.

The Chinese translation of flag means flag, signal flag, flag means to indicate an uplifting determination or action.

!: The meaning of right or wrong, adding this symbol in front of a variable or value is the meaning of taking a wrong for this variable.

If the variable or value is a Boolean type: for example! false is true, !true is false.

If the variable is of other types, any non-0 number is false, and 0 is true.

Complex expressions, such as! (a==b), that is, the calculation in parentheses is true or false, and then the non is not. For example, a=1, b=2, a==b is false, !(a==b) is true.

flag is to see whether the value of the flag is true or false, so flag=0 in the question, then! flag is true.

In c, a variable flag is generally set, which is a variable to represent judgment, which is used as a flag. For example, in the case of all the time, the flag is set to 1, and in the other case, the flag is set to 2. The variable is called flag, which is just a matter of habit, and it can also be called something else.

flag is generally a variable defined by oneself, which is the meaning of the flag. General Usage:

Example: If light 1 is on, then the buzzer will go off for 1 second.

if (light 1 is on).

flag = 1；

if(flag) is actually a sign made artificially if light 1 is on.

This is a concise way to zero a bit of the variable flag, as follows:

flag = flag & 0x01 "If flag = 0x47; n = 2;

0x47 & 0x01<<2));

0x47 & 0x04);

0x47 & 0xfb;

0x43;The result of the final flag is 0x43

A flag is generally a shape used to mark.

It's the negation!flag is generally used in judgment.

For example, flag = 0;

if(!flag) is true to execute the content of if.

First question:

There is such a question.

int a=13,b=64；

printf("%d",!a||b>>3)；

Looking for answers? The output is: 1

Because! is a logical non-operator, !A is "not A".

That is, when a=0, !a=1;a≠0,!a=0。

b>>3;is b shifted 3 bits to the right, which is equivalent to b divided by 8.

It's logic or operators, so! a||b>>3 means! a=1 or b>>3≠0.

If it is established, it will return 1, and if it is not established, it will return 0 b=64; 64/8=8;

So in this question! a||b>>3 is true, and the result of the output is naturally 1 The second question:

C language! What does flag mean.

Also, I would like to ask if flag=0 is defined

if(!flag) means?

First, let's talk about why it's flag:

The flag variable is not built into c, it is defined by a programmer using c (like you), which is the meaning of the variable itself, and it is a good variable name style.

Generally marked right and wrong, if you want to learn more about this, learn it yourself, Google it yourself!

So! flag means flag=0;

if(!flag) is if(flag==0).

The original meaning of the word flag is: flag, sign.

This is a flag ... Just one variable ...

int flag=0;

Didn't notice??

flag is generally a variable defined by oneself, which is the meaning of the flag. General Usage:

Example: If light 1 is on, then the buzzer will go off for 1 second.

if (light 1 is on) flag

if（flag

Actually, if the light 1 is on.

flag0;(Don't forget to clear zero).

Buzzer sounds; Delay 1 second;

buzzer off; In fact, it is an artificially made marker.