Can you solve this equation?
Time Limit: 2000/1000 MS (java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 19266 Accepted Submission(s): 8484
PRoblem Description Now,given the equation 8*x^4 + 7*x^3 + 2*x^2 + 3*x + 6 == Y,can you find its solution between 0 and 100; Now please try your lucky.
Input The first line of the input contains an integer T(1<=T<=100) which means the number of test cases. Then T lines follow, each line has a real number Y (fabs(Y) <= 1e10);
Output For each test case, you should just output one real number(accurate up to 4 decimal places),which is the solution of the equation,or “No solution!”,if there is no solution for the equation between 0 and 100.
Sample Input 2 100 -4
Sample Output 1.6152 No solution!
#include<cstdio>#include<math.h>double h(double x){ return 8*pow(x,4)+7*pow(x,3)+2*pow(x,2)+3*x+6;}int main(){ int t; scanf("%d",&t); while(t--) { double y; scanf("%lf",&y); if(y>=h(0)&&y<=h(100)) /// 保证y值的范围 { double l=0; ///二分思想 double r=100; while(r-l>1e-7) ///注意精度 { double m=(l+r)/2.0; if(h(m)<y) { l=m+1e-8; } else { r=m-1e-8; } }printf("%.4lf/n",(l+r)/2.0); } else printf("No solution!/n"); }}新闻热点
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