Can you solve this equation?
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 12798 Accepted Submission(s): 5716
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
1 #include <cmath> 2 #include <cstdio> 3 #include <iostream> 4 using namespace std; 5 double f(double x) 6 { 7 return 8*x*x*x*x + 7*x*x*x + 2*x*x + 3*x + 6; 8 } 9 int main() 10 { 11 int t; double y, mid; 12 scanf("%d", &t); 13 while(t--) 14 { 15 scanf("%lf", &y); 16 if(y<f(0) || y>f(100)) 17 { 18 printf("No solution! "); 19 continue; 20 } 21 double left=0.0, right = 100.0; 22 while(right - left > 1e-8) 23 { 24 mid = (right + left) / 2.0; 25 if(abs(abs(f(mid))-y) < 1e-6) 26 break; 27 if(f(mid) < y) left = mid; 28 else right = mid; 29 } 30 printf("%.4lf ", mid); 31 32 } 33 return 0; 34 }