题意:有点长,意思是说有一个鸟,在两列火车之间不停的来回飞,两列相距为d时,都开始减速,直到最后停止下来,正好是相距0米,
现在给定两列车的速度和减速时的加速度,和鸟的速度求 d 和鸟飞过的路程。
析:就是一个简单的追及相遇问题,注意的是求的飞行时间时,要计算两列火车制动时间最长的那个。
代码如下:
#pragma comment(linker, "/STACK:1024000000,1024000000") #include <cstdio> #include <string> #include <cstdlib> #include <cmath> #include <iostream> #include <cstring> #include <set> #include <queue> #include <algorithm> #include <vector> #include <map> #include <cctype> #include <cmath> #include <stack> #include <sstream> #define debug() puts("++++"); #define gcd(a, b) __gcd(a, b) #define lson l,m,rt<<1 #define rson m+1,r,rt<<1|1 #define freopenr freopen("in.txt", "r", stdin) #define freopenw freopen("out.txt", "w", stdout) using namespace std; typedef long long LL; typedef unsigned long long ULL; typedef pair<int, int> P; const int INF = 0x3f3f3f3f; const LL LNF = 1e16; const double inf = 0x3f3f3f3f3f3f; const double PI = acos(-1.0); const double eps = 1e-8; const int maxn = 1e5 + 10; const int mod = 1e9 + 7; const int dr[] = {-1, 0, 1, 0}; const int dc[] = {0, 1, 0, -1}; const char *de[] = {"0000", "0001", "0010", "0011", "0100", "0101", "0110", "0111", "1000", "1001", "1010", "1011", "1100", "1101", "1110", "1111"}; int n, m; const int mon[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; const int monn[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; inline bool is_in(int r, int c){ return r >= 0 && r < n && c >= 0 && c < m; } int main(){ int T; cin >> T; for(int kase = 1; kase <= T; ++kase){ double v1, v2, v3, a1, a2; cin >> v1 >> v2 >> v3 >> a1 >> a2; double d = v1 * v1 / (2.0*a1) + v2 * v2 / (2.0*a2); double ans = v3 * max(v1 / a1, v2 / a2); printf("Case %d: %.10f %.10f\n", kase, d, ans); } return 0; }