求C语言大佬帮忙 我是入门小白

Question

这个怎么把for文转变为while文 #include #include #define E 0.00001 extern double f(double x); void main() { double a=-3.0,b=3.0,c; for(;;) { if(fabs(b-a) < E) break; c=(a+b)/2.0; if(f(c)==0.0) break; else if(f(a)*f(c) > 0.0) a=c; else b=c; } printf("x=%10.5f\n",c); } double f(double x) { return(x*x*x+3.0*x*x+3.0*x+1.0); }

Answer 1

for(;;)换成whie(true)就可以了。代码如下：

#include <math.h>
#include <stdio.h>
#define E 0.00001 
extern double f(double x); 
void main() 
{ 
	double a=-3.0,b=3.0,c; 
	while(true) //for(;;) 
	{ 
		if(fabs(b-a) < E) 
			break; 
		c=(a+b)/2.0; 
		if(f(c)==0.0) 
			break; 
		else if(f(a)*f(c) > 0.0) 
			a=c; 
		else b=c; 
	} 
	printf("x=%10.5f\n",c); 
} 
double f(double x) 
{ 
	return(x*x*x+3.0*x*x+3.0*x+1.0); 
}