Codeforces 590B Chip 'n Dale Rescue Rangers（二分）

Codeforces 590B Chip 'n Dale Rescue Rangers（二分）

题目链接：Codeforces 590B Chip ‘n Dale Rescue Rangers

解题思路

二分时间，判断是否可行。判断方法为先处理出在风的作用下会移动到哪里，然后看最后用最大速度是否能到达目的地。

代码

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>using namespace std;
const double eps = 1e-8;double sx, sy, ex, ey;
double v, t;
double vx, vy, wx, wy;bool judge (double h) {if (h > t) {sx = ex - vx * t - (h-t) * wx;sy = ey - vy * t - (h-t) * wy;} else {sx = ex - vx * h;sy = ey - vy * h;}return sx * sx + sy * sy <= v * v * h * h;
}int main () {scanf("%lf%lf%lf%lf", &sx, &sy, &ex, &ey);scanf("%lf%lf", &v, &t);scanf("%lf%lf%lf%lf", &vx, &vy, &wx, &wy);ex -= sx, ey -= sy;double l = 0, r = 1e20;while (r - l > eps) {double mid = (l + r) * 0.5;if (judge(mid))r = mid;elsel = mid;}printf("%.10lfn", l);return 0;
}