<C Primer Pus>6 Using Relational Operators and Exprssions

 1 while(number < 6){
 2     printf("Your number is too small.\n");
 3     scanf("%d", &number);                
 4 }
 5 
 6 
 7 while(ch != '$'){
 8     count++;
 9     scanf("%c", &ch);
10 }    
11 
12 
13 while(scanf("%f", &num) == 1){
14     sum = sum +num;
15 }

 1 #include <stdio.h>
 2 #include <math.h>
 3 int main(void){
 4     const double ANSWER = 3.14159;
 5     double respone;
 6 
 7     scanf("%lf", &respone);
 8     while (fabs(respone - ANSWER) > 0.0001){
 9         printf("Try again.\n");
10         scanf("%lf", &respone);
11     }
12 
13     printf("Close enough.\n");
14 
15     return 0;
16 }

REMEBER :

You should limit yourself to using only < and > in floating-point comparisons.

while(status == 1)  is ture.  and  while(status = 1) is ture ....so advice to write like that  while(1 == status).

转载于:https://www.cnblogs.com/michael2016/p/6658693.html