Can You solve this equation?
Time limit:2000/1000 MS (java/others) Memory limit:32768/32768 K (java/others)
Total submission (s): 12794 Accepted Submission (s): 5715
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 10 0;
Now 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);
Should just output one real number (accurate up to 4 decimal places), which is the solution O f 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!
The title says that the value of x is within [0,100], so be judged properly y<6 | | y>807020306, Output no solution! And then do a binary search.
The code is as follows:
#include <cstdio>
#include <cmath>
int find (double x,double y)
{
if (Y (8.0*pow (x,4) +7.0 *pow (x,3) +2.0*pow (x,2) +3.0*x+6)
return 1;
else
return 0;
}
int main ()
{
int t;
Double y,mid,l,r;
scanf ("%d", &t);
while (t--)
{
l=0;
r=100;
scanf ("%lf", &y);
if (y<6| | y>807020306)
printf ("No solution!\n");
else
{
while (r-l>1e-8)
{
mid= (r+l)/2.0;
if (find (mid,y))//return value of 1 indicates that the value of x is larger, then continue to find r=mid in the interval less than mid
;
else
l=mid;
}
printf ("%.4lf\n", mid);
}
}
return 0;
}