c语言if else语句

Find the output of the following programs,

查找以下程序的输出，

Program 1)

程序1)

#include 
    
     int main(){
       int x = 400, y, z;    if (x >= 500)        y = 400;    z = 300;    printf("%d %d\n", y, z);    return 0;}
    

Output

输出量

32766 300

Explanation:

说明：

In the code, the condition x>=500 is false, so the variable y will not be assigned and the statement z=300 is written after the conditional statement, so it will be assigned with 300. Thus, the value of y will be a garbage value and value of z will be 300.

在代码中，条件x> = 500为假，因此将不分配变量y，并且在条件语句之后写入语句z = 300 ，因此将其分配为300。因此， y的值将为垃圾值和z的值为300。

Program 2)

程序2)

#include 
    
     int main(){
       int p = 800, q, r;    if (p >= 700)        q = 600;    r = 500;    printf("%d %d\n", q, r);    return 0;}
    

Output

输出量

600 500

Explanation:

说明：

In the code, the condition p>=700 is true, so the variable q will be assigned with the value 600 and the statement r=500 is written after the conditional statement, so it will be assigned with 500. Thus, the value of q will be a 600 value and value of r will be 500.

在代码中，条件p> = 700为true，因此将为变量q分配值600，并在条件语句后写入语句r = 500 ，因此将其分配为500。因此， q将是600的值，而r的值将是500。

Program 3)

程序3)

#include 
    
     int main(){
       int a = 30, b = 40;    if (a == b);    printf("%d %d\n", a, b);    return 0;}
    

Output

输出量

30 40

Explanation:

说明：

In the code, the condition if(a==b); is terminated with semicolon so the statement printf("%d %d\n",a,b); will not be consider as a body of the if statement. Thus, the program will print the value of a and b.

在代码中，条件为if(a == b); 以分号终止，因此语句printf(“％d％d \ n”，a，b); 不会被视为if语句的主体。 因此，程序将打印a和b的值。

Program 4)

程序4)

#include 
    
     int main(){
       int e = 4;    float f = 4.0;    if (e == f) {
           printf("E and F are equal\n");    }    else {
           printf("E and F are not equal");    }    return 0;}
    

Output

输出量

E and F are equal

Explanation:

说明：

In the code, variable e is an integer type and variable f is a float type, while comparing them with an if statement (if(e==f)), the value of f will be truncated to an integer (due to implicit type conversion). Thus, the condition will be true and "E and F are equal" will be printed.

在代码中，变量e是整数类型，变量f是浮点类型，将它们与if语句( if(e == f) )进行比较时， f的值将被截断为整数(由于隐式类型)转换)。 因此，条件为真， 并且将打印“ E和F相等” 。

Program 5)

程序5)

#include 
    
     int main(){
       int p = 4, q, r;    q = p = 15;    r = p < 15;    printf("p = %d q = %d r = %d\n", p, q, r);    return 0;}
    

Output

输出量

p = 15 q = 15 r = 0

Explanation:

说明：

In the code, the statement q = p = 15; is assigning 15 to the variables p and q and the statement r = p<15; is assigning 0 to the variable r because p is not less than 15 (condition is false). Thus, the value of p, q and r will be 15, 15, and 0.

在代码中，语句q = p = 15; 将变量p和q赋值为15，并且语句r = p <15； 因为p不小于15(条件为假)，所以将0赋给变量r 。 因此， p ， q和r的值将分别为15、15和0。

Program 6)

计划6)

#include 
    
     int main(){
       int i = 65;    char j = 'A';    if (i == j) {
           printf("This place is beautiful\n");    }    else {
           printf("This place is not beautiful\n");    }    return 0;}
    

Output

输出量

This place is beautiful

Explanation:

说明：

The character variable stores the ASCII code of the given character (it's also a number type of variable). Thus, the value of j will be 65 (The ASCII Code of 'A' is 65). So the condition if(i==j) will be true and "This place is beautiful" will be printed.

字符变量存储给定字符的ASCII码(它也是变量的数字类型)。 因此， j的值为65(“ A”的ASCII码为65)。 因此条件if(i == j)将为true，并且将打印“这个地方很漂亮” 。

Program 7)

计划7)

#include 
    
     int main(){
       float p = 13.25, q = 14.5;    if (p = q) {
           printf("Hello\n");    }    return 0;}
    

Output

输出量

Hello

Explanation:

说明：

In the statement if(p=q), p=q is not a comparison operation, we used = (assignment operator), thus the value of q will be assigned into p and the statement will be evaluated to 14.5 which is a non-zero value and conditional will be true.

在语句if(p = q) ， p = q不是比较运算的情况下，我们使用= (赋值运算符)，因此q的值将分配给p，并且该语句的计算结果为14.5 ，这不是零值和条件将为真。

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c语言if else语句