acm-Two-point search can solve this equation?—— hdu2199

Can You solve this equation? Time limit:2000/1000 MS (java/others) Memory limit:32768/32768 K (java/others)
Total submission (s): 7507 Accepted Submission (s): 3490

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! Author Redow Title: http://acm.hdu.edu.cn/showproblem.php?pid=2199
The topic is just beginning to think that it is computational geometry, but out of the search topic, you will know to use search to do ... Then analyze what kind of search. The foundation of the Bfs,dfs certainly not, even BFS are not two-way BFS that is not even think. A *, ida* look may be a bit of a meaning ... But don't forget that there is a binary search = =. Well, this problem is solved by two points. Control the accuracy, for the accuracy of judgment (my understanding): I think is, with printf directly output a double type, general output to 6 decimal places, I think is the default reserved six decimal places, so the accuracy set 1e-6. But the YM is because: the topic required to retain four decimal places, generally will be expanded two decimal places to prevent rounding, etc., so retain 6 decimal places. Anyway this problem is guaranteed six decimal places, there is a point to spit groove, just start not to look at the test data carefully, see 1.615, and then handed, AC found my input 100 will come to 1.6151 ... The example of the problem is 6.6152 O (╯-╰) o ....
This is not water over = = ... Again, there is no boundary in the test data of this topic ... is when Y is 6 or 8XXXXXX. (Y with x equal to 100 in the equation)

/************************************** *************************************** * Author:Tree                     * *from:http://blog.csdn.net/lttree * * Title:can solve this equation?* *source:hdu 2119 * * Hint: Two-point search * *************************************** ********************************* /#include <stdio.h> #define EPS 1e-6 double Jdz (double a) {return a<0?-a:a;} double Calcu (double X
    {return 8*x*x*x*x+7*x*x*x+2*x*x+3*x+6;} double binary_s (int y) {double l,h,m;
    l=0,h=100;
        while (h-l>eps) {m= (l+h)/2.0;
        if (CALCU (m) >y) h=m;
    else l=m;
} return (L+H)/2.0;
    } int main () {int test,y;
    scanf ("%d", &test);
        while (test--) {scanf ("%d", &y);
        if (y<=6 | | Y>=CALCU ()) printf ("No solution!\n");
    else printf ("%.4lf\n", binary_s (y));
} return 0; }