Can you solve this equation?
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 4814 Accepted Submission(s): 2247
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.
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!
Author
Redow
Recommend
lcy
#include<iostream> #include<cstdio> #include<cstring> using namespace std; const double eps=1e-10; double y; double f(double x){ return 8*x*x*x*x+7*x*x*x+2*x*x+3*x+6-y; } int main(){ //freopen("input.txt","r",stdin); int t; scanf("%d",&t); while(t--){ scanf("%lf",&y); double l=0,r=100,mid; if(f(l)>eps || f(r)<eps){ puts("No solution!"); continue; } while(l+eps<=r){ mid=(l+r)/2; if(f(mid)<eps) l=mid+eps; else r=mid-eps; } printf("%.4lf\n",l); } return 0; }