HDU 2199--can You solve this equation? Two points water problem

Can You solve this equation? Time limit:2000/1000 MS (java/others) Memory limit:32768/32768 K (java/others)
Total submission (s): 13018 Accepted Submission (s): 5835


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!

#include <cstdio>
#include <cmath>

double Change (double x) {
	 return 8 * POW (x, 4) + 7 * POW (x, 3) + 2 * POW (x, 2) + 3 * x + 6; 
}

int main () {
	int  T;
	scanf ("%d", &t);
	while (t--) {
		double sum;
		scanf ("%lf", &sum);
		Double L = 0, r = +;
		if (Sum < change (0) | |-sum > Change (100.0)) {
			printf ("No solution!\n");
			Continue;
		}
		else{
			while (R-l > 1e-6) {
				double mid = (L + r)/2;
				if (change (mid) > sum)
					r = Mid;
				else 
					L = mid;
			}
			printf ("%.4lf\n", R);
		}
	}
	return 0;
}