UVA 10341 Solve It 解方程 二分查找+精度
题意:给出一个式子以及里面的常量,求出范围为[0,1]的解,精度要求为小数点后4为。
二分暴力查找即可。
e^(-n)可以用math.h里面的exp(-n)表示。
代码:(uva该题我老是出现Submission Error,过几天再试看看)
/* * Author: illuz <iilluzen@gmail.com> * Blog: http://blog.csdn.net/hcbbt * File: uva10241.cpp * Lauguage: C/C++ * Create Date: 2013-08-25 15:37:46 * Descripton: UVA 10341 Solve It, bisection */ #include <cstdio> #include <cstdlib> #include <cstring> #include <cmath> #include <iostream> #include <list> #include <vector> #include <map> #include <set> #include <deque> #include <queue> #include <stack> #include <utility> #include <algorithm> using namespace std; #define rep(i, n) for (int i = 0; i < (n); i++) #define repu(i, a, b) for (int i = (a); i < (b); i++) #define repf(i, a, b) for (int i = (a); i <= (b); i++) #define repd(i, a, b) for (int i = (a); i >= (b); i--) #define swap(a, b) {int t = a; a = b; b = t;} #define mc(a) memset(a, 0, sizeof(a)) #define ms(a, i) memset(a, i, sizeof(a)) #define sqr(x) ((x) * (x)) #define FI(i, x) for (typeof((x).begin()) i = (x).begin(); i != (x).end(); i++) typedef long long LL; typedef unsigned long long ULL; /****** TEMPLATE ENDS ******/ double p, q, r, s, t, u; #define calc(x) (p*exp(-x)+q*sin(x)+r*cos(x)+s*tan(x)+t*x*x+u) int main() { while (scanf("%lf%lf%lf%lf%lf%lf", &p, &q, &r, &s, &t, &u)) { if (calc(0) < 0 || calc(1) > 0) printf("No solution\n"); else { double x1 = 0, x2 = 1; while (abs(x1 - x2) >= 1e-10) { double x = (x1 + x2) / 2.0; if (calc(x) > 0) x1 = x; else x2 = x; } printf("%.4lf\n", x1); } } return 0; }