The Snail
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 726 Accepted Submission(s): 544
Problem Description
A
snail is at the bottom of a 6-foot well and wants to climb to the top.
The snail can climb 3 feet while the sun is up, but slides down 1 foot
at night while sleeping. The snail has a fatigue factor of 10%, which
means that on each successive day the snail climbs 10% * 3 = 0.3 feet
less than it did the previous day. (The distance lost to fatigue is
always 10% of the first day's climbing distance.) On what day does the
snail leave the well, i.e., what is the first day during which the
snail's height exceeds 6 feet? (A day consists of a period of sunlight
followed by a period of darkness.) As you can see from the following
table, the snail leaves the well during the third day.
Day Initial Height Distance Climbed Height After Climbing Height After Sliding
1 0 3 3 2
2 2 2.7 4.7 3.7
3 3.7 2.4 6.1 -
Your job is to solve this problem in general. Depending on the parameters of the problem, the snail will eventually either leave the well or slide back to the bottom of the well. (In other words, the snail's height will exceed the height of the well or become negative.) You must find out which happens first and on what day.
Day Initial Height Distance Climbed Height After Climbing Height After Sliding
1 0 3 3 2
2 2 2.7 4.7 3.7
3 3.7 2.4 6.1 -
Your job is to solve this problem in general. Depending on the parameters of the problem, the snail will eventually either leave the well or slide back to the bottom of the well. (In other words, the snail's height will exceed the height of the well or become negative.) You must find out which happens first and on what day.
Input
The
input file contains one or more test cases, each on a line by itself.
Each line contains four integers H, U, D, and F, separated by a single
space. If H = 0 it signals the end of the input; otherwise, all four
numbers will be between 1 and 100, inclusive. H is the height of the
well in feet, U is the distance in feet that the snail can climb during
the day, D is the distance in feet that the snail slides down during the
night, and F is the fatigue factor expressed as a percentage. The snail
never climbs a negative distance. If the fatigue factor drops the
snail's climbing distance below zero, the snail does not climb at all
that day. Regardless of how far the snail climbed, it always slides D
feet at night.
Output
For
each test case, output a line indicating whether the snail succeeded
(left the well) or failed (slid back to the bottom) and on what day.
Format the output exactly as shown in the example.
Sample Input
6 3 1 10
10 2 1 50
50 5 3 14
50 6 4 1
50 6 3 1
1 1 1 1
0 0 0 0
Sample Output
success on day 3
failure on day 4
failure on day 7
failure on day 68
success on day 20
failure on day 2
Source
Recommend
Eddy
1 // Project name : 1302 ( The Snail ) 2 // File name : main.cpp 3 // Author : Izumu 4 // Date & Time : Sun Jul 8 19:11:58 2012 5 6 #include <iostream> 7 using namespace std; 8 9 double H,U,D,F,height; 10 11 /**************************************************************/ 12 int Days() 13 { 14 int day = 1; 15 double step = U * F / 100; 16 height = 0; 17 while(true) 18 { 19 height += (U-D); 20 if (height >= H) return day; 21 else if(height < 0) return -day; 22 U -= step; 23 if(U<0) U = 0; 24 day++; 25 } 26 } 27 28 /**************************************************************/ 29 int main() 30 { 31 while (cin >> H >> U >> D >> F && H) 32 { 33 int day = Days(); 34 if(day > 0) cout << "success on day " << day - 1 << endl; 35 else cout << "failure on day " << -day << endl; 36 } 37 return 0; 38 } 39 40 41 // end 42 // ism