水题 Codeforces Round #105 (Div. 2) B. Escape

 

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 1 /*  2  水题：这题唯一要注意的是要用double，princess可能在一个小时之内被dragon赶上  3 */  4 #include <cstdio>  5 #include <algorithm>  6 #include <cstring>  7 #include <cmath>  8 #include <vector>  9 #include <map> 10 using namespace std; 11 12 const int MAXN = 1e4 + 10; 13 const int INF = 0x3f3f3f3f; 14 15 int main(void) //Codeforces Round #105 (Div. 2) B. Escape 16 { 17 //freopen ("B.in", "r", stdin); 18 19 double vp, vd, t, f, c; 20 while (scanf ("%lf%lf%lf%lf%lf", &vp, &vd, &t, &f, &c) == 5) 21  { 22 if (vd <= vp) puts ("0"); 23 else 24  { 25 double cur = vp * t; double d = 0; 26 int cnt = 0; 27 while (cur < c) 28  { 29 if (cur + vp <= d + vd) 30  { 31 double time = (cur - d) / (vd - vp); 32 if (cur + time * vp >= c) break; 33 cur += vp * (time + (d + vd * time) / vd + f); d = 0; 34 cnt++; 35  } 36 else 37  { 38 cur += vp; d += vd; 39  } 40  } 41 42 printf ("%d\n", cnt); 43  } 44  } 45 46 return 0; 47 }