Can you solve this equation? Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 16281 Accepted Submission(s): 7206 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. 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
数学题，直接二分，代码
1 #include"iostream" 2 #include"algorithm" 3 #include"cstdio" 4 #include"cstring" 5 #include"cmath" 6 #define max(a,b) a>b?a:b 7 #define min(a,b) a<b?a:b 8 #define MX 10000 + 50 9 using namespace std; 10 11 double f(double x) 12 { 13 return 8*pow(x,4)+7*pow(x,3)+2*pow(x,2)+3*x+6; 14 } 15 16 int main() 17 { 18 int n; 19 double m; 20 while(~scanf("%d",&n)) 21 { 22 for(int k=1; k<=n; k++) 23 { 24 scanf("%lf",&m); 25 26 double i=0.0; 27 if(m<f(0)||m>f(100)) 28 { 29 printf("No solution! ");continue; 30 } 31 double fr=0.0,ed=100.0; 32 for(; fabs(f(fr)-f(ed))>1e-4;) 33 { 34 i=(fr+ed)/2; 35 if(f(i)<m)fr=i; 36 else ed=i; 37 } 38 { 39 printf("%.4lf ",i); 40 } 41 } 42 } 43 return 0; 44 }