二分法求根

Posted 2021-11-25 zhishoumuguinian

 1 #include<stdio.h>
 2 #include<math.h>
 3 float f(float x){
 4     return (x*x*x-x-1);
 5 }
 6 int main(){
 7     float x1, x2;
 8     scanf("%f,%f", &x1, &x2);
 9     
10     float cen=(x1+x2)/2.0;
11     float vc=f(cen);
12     while(fabs(vc) > 1e-6){
13         
14         if(vc > 0){
15             x2=cen;
16         }else if(vc < 0){
17             x1=cen;
18         }else{
19             break;
20         }
21         
22         cen=(x1+x2)/2.0;
23         vc=f(cen);
24     } 
25     printf("x=%6.2f\n", cen);
26 }