The difference between = and == in c language

In C language "=" is used for assignment and "==" is used for comparison. "=" assigns the value on the right to the variable on the left, while "==" compares the values ​​of two expressions and returns true if they are equal, false otherwise.

The difference between = and == in C language

The assignment operators "=" and The comparison operator "==" is two different operators with different functions.

The function of assignment operator =

• Assigns the value of the expression on the right to the variable on the left.
• The assignment operation is a left associative operation, which means that it is performed from left to right.

For example:

<code class="c">int x = 5; // 将 5 赋值给变量 x</code>

Function of comparison operator==

• Compare two expressions The value of the formula returns true (1) if they are equal, otherwise returns false (0).
• The comparison operator is an infix operator, which means it is between the two operands.

For example:

<code class="c">int x = 5;
int y = 5;

if (x == y) {
  // x 和 y 相等，执行此代码块
}</code>

Difference

The following is the difference between "=" and "==" Main difference:

• Function: "=" assignment, while "==" comparison.
• Operator type: "=" is the assignment operator, while "==" is the comparison operator.
• Return type: "=" returns the variable value after assignment, while "==" returns 0 (false) or 1 (true).
• Execution order: "=" is executed from left to right, while "==" is executed sequentially.

Usage scenarios

Usually "=" is used for assignment, and "==" is used for comparison. The specific usage scenarios are as follows:

• Use "=" to initialize variables, store temporary values ​​or update variable values.
• Use "==" to compare variables, array elements, or expressions.

Note:

• In other programming languages, "=" may be used for both assignment and comparison, but in C language, they are different operators.
• Abusing "=" and "==" can lead to code errors, so it's important to understand their difference.

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