C if statement

Analyzing C

If a Boolean expression followed by a statementby the one or more statements.

grammar

If the C language syntax statements:

if(boolean_expression)
{
   /* 如果布尔表达式为真将执行的语句 */
}

If the Boolean expression istrue, the if statement within a block of code will be executed.If the Boolean expression isfalse, if the first set of codes after the statement (after the close parenthesis) will be executed.

C language to anynon-zero and non-nullvalue is assumed to betrue,thezeroornullassumed to befalse.

flow chart

Examples

#include <stdio.h>
 
int main ()
{
   /* 局部变量定义 */
   int a = 10;
 
   /* 使用 if 语句检查布尔条件 */
   if( a < 20 )
   {
       /* 如果条件为真，则输出下面的语句 */
       printf("a 小于 20\n" );
   }
   printf("a 的值是 %d\n", a);
 
   return 0;
}

When the above code is compiled and executed, it produces the following results:

a 小于 20
a 的值是 10

Analyzing C