c语言中的逻辑运算符

逻辑运算符 (Logical Operators)

Logical operators are used to check the combinations of the two conditional expressions.

逻辑运算符用于检查两个条件表达式的组合。

The following are the types of logical operators.

以下是逻辑运算符的类型 。

1. Logical AND (&&) Operator

   逻辑AND( && )运算符

2. Logical OR (||) Operator

   逻辑OR( || )运算符

3. Logical NOT (!) Operator

   逻辑NOT( ！ )运算符

1)逻辑AND(&&)运算符 (1) Logical AND (&&) Operator)

Logical AND operator represented by the symbols "&&", it works with two operands and returns 1 if both operands are true (non-zero); 0, otherwise.

逻辑AND运算符由符号“ && ”表示，它与两个操作数一起使用，如果两个操作数均为true(非零)，则返回1；否则，返回1。 0，否则。

Note: Operands can be values, conditions, expressions, etc.

注意 ：操作数可以是值，条件，表达式等。

Syntax:

句法：

operand1 && operand2

Truth table:

真相表：

operand1	operand2	operand1 && operand2
Non-zero	Non-zero	1
Non-zero	0	0
0	Non-zero	0
0	0	0

操作数1	操作数2	操作数1 &&操作数2
非零	非零	1个
非零	0	0
0	非零	0
0	0	0

C++ program to demonstrate the example of logical AND (&&) operator

C ++程序演示逻辑AND(&&)运算符的示例

#include <iostream>
using namespace std;

int main()
{
    int a = 10;
    int b = 20;

    // printing the values
    cout << "a : " << a << endl;
    cout << "b : " << b << endl;
    cout << endl;

    // Logical AND operations
    cout << "(a && b) : " << (a && b) << endl;
    cout << "(a && 0) : " << (a && 0) << endl;
    cout << "(0 && b) : " << (0 && b) << endl;
    cout << "(0 && 0) : " << (0 && 0) << endl;
    cout << endl;

    cout << "(a >= 10 && b <= 30) : " << (a >= 10 && b <= 30) << endl;
    cout << "(a == 10 && b == 20) : " << (a == 10 && b == 20) << endl;
    cout << "(a >= 10 && b == 30) : " << (a >= 10 && b == 30) << endl;
    cout << "(a < 10 && b < 20)   : " << (a < 10 && b < 20) << endl;

    return 0;
}

Output:

输出：

a : 10
b : 20

(a && b) : 1
(a && 0) : 0
(0 && b) : 0
(0 && 0) : 0

(a >= 10 && b <= 30) : 1
(a == 10 && b == 20) : 1
(a >= 10 && b == 30) : 0
(a < 10 && b < 20)   : 0

2)逻辑或(||)运算符 (2) Logical OR (||) Operator)

Logical OR operator represented with the symbols "||", it works with two operands and returns 1 if one (or both) operands are true (non-zero); 0, otherwise.

用符号“ || ”表示的逻辑“或”运算符 ，可用于两个操作数，如果一个(或两个)操作数为真(非零)，则返回1；否则，返回1。 0，否则。

Syntax:

句法：

operand1 || operand2

Truth table:

真相表：

operand1	operand2	operand1 && operand2
Non-zero	Non-zero	1
Non-zero	0	1
0	Non-zero	1
0	0	0

操作数1	操作数2	操作数1 &&操作数2
非零	非零	1个
非零	0	1个
0	非零	1个
0	0	0

C++ program to demonstrate the example of logical OR (||) operator

C ++程序演示逻辑OR(||)运算符的示例

#include <iostream>
using namespace std;

int main()
{
    int a = 10;
    int b = 20;

    // printing the values
    cout << "a : " << a << endl;
    cout << "b : " << b << endl;
    cout << endl;

    // Logical OR operations
    cout << "(a || b) : " << (a || b) << endl;
    cout << "(a || 0) : " << (a || 0) << endl;
    cout << "(0 || b) : " << (0 || b) << endl;
    cout << "(0 || 0) : " << (0 || 0) << endl;
    cout << endl;

    cout << "(a >= 10 || b <= 30) : " << (a >= 10 || b <= 30) << endl;
    cout << "(a == 10 || b == 20) : " << (a == 10 || b == 20) << endl;
    cout << "(a >= 10 || b == 30) : " << (a >= 10 || b == 30) << endl;
    cout << "(a < 10 || b < 20)   : " << (a < 10 || b < 20) << endl;

    return 0;
}

Output:

输出：

a : 10
b : 20

(a || b) : 1
(a || 0) : 1
(0 || b) : 1
(0 || 0) : 0

(a >= 10 || b <= 30) : 1
(a == 10 || b == 20) : 1
(a >= 10 || b == 30) : 1
(a < 10 || b < 20)   : 0

3)逻辑非(！)运算符 (3) Logical NOT (!) Operator)

Logical NOT operator represented by the symbols "!", it works with one operand and returns 1 if the operand is zero;0, otherwise.

逻辑NOT运算符以符号“ ！ ”表示，它与一个操作数一起使用，如果操作数为零，则返回1；否则返回0。

Syntax:

句法：

!operand

Truth table:

真相表：

operand	!operand
Non-zero	0
0	1

操作数	！operand
非零	0
0	1个

C++ program to demonstrate the example of logical NOT (!) operator

C ++程序演示逻辑NOT(！)运算符的示例

#include <iostream>
using namespace std;

int main()
{
    int a = 10;
    int b = 0;

    // printing the values
    cout << "a : " << a << endl;
    cout << "b : " << b << endl;
    cout << endl;

    cout << "!a : " << !a << endl;
    cout << "!b : " << !b << endl;
    cout << endl;

    // Logical NOT operations
    cout << "!(a || b) : " << !(a || b) << endl;
    cout << "!(a || 0) : " << !(a || 0) << endl;
    cout << "!(0 || b) : " << !(0 || b) << endl;
    cout << "!(0 || 0) : " << !(0 || 0) << endl;
    cout << endl;

    cout << "!(a >= 10 || b <= 30) : " << !(a >= 10 || b <= 30) << endl;
    cout << "!(a == 10 || b == 20) : " << !(a == 10 || b == 20) << endl;
    cout << "!(a >= 10 || b == 30) : " << !(a >= 10 || b == 30) << endl;
    cout << "!(a < 10 || b < 20)   : " << !(a < 10 || b < 20) << endl;

    return 0;
}

Output:

输出：

a : 10
b : 0

!a : 0
!b : 1

!(a || b) : 0
!(a || 0) : 0
!(0 || b) : 1
!(0 || 0) : 1

!(a >= 10 || b <= 30) : 0
!(a == 10 || b == 20) : 0
!(a >= 10 || b == 30) : 0
!(a < 10 || b < 20)   : 0

翻译自: https://www.includehelp.com/cpp-tutorial/logical-operators-in-c-cpp.aspx

c语言中的逻辑运算符