Can you solve this equation?
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 12766 Accepted Submission(s):
5696
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<stdio.h> #include<string.h> double f(double v)//用来计算方程结果(即y的值) { return 8*v*v*v*v+7*v*v*v+2*v*v+3*v+6; } int main() { int t; double y,l,r,mid; scanf("%d",&t); while(t--) { scanf("%lf",&y); if(y<f(0)||y>f(100)) { printf("No solution!\n"); continue; } l=0;r=100;mid=0; while((r-l) > 1e-10)//题目要求精度为小数点后四位,最好把精度调高 { mid=(l+r)/2;//每次折半取x的范围 if(f(mid) < y) l=mid; else r=mid; } printf("%.4lf\n",mid); } }
时间: 2024-10-10 09:44:41