Tasks Details
easy
1.
FrogJmp
Count minimal number of jumps from position X to Y.
Task Score
100%
Correctness
100%
Performance
100%
A small frog wants to get to the other side of the road. The frog is currently located at position X and wants to get to a position greater than or equal to Y. The small frog always jumps a fixed distance, D.
Count the minimal number of jumps that the small frog must perform to reach its target.
Write a function:
class Solution { public int solution(int X, int Y, int D); }
that, given three integers X, Y and D, returns the minimal number of jumps from position X to a position equal to or greater than Y.
For example, given:
X = 10 Y = 85 D = 30the function should return 3, because the frog will be positioned as follows:
- after the first jump, at position 10 + 30 = 40
- after the second jump, at position 10 + 30 + 30 = 70
- after the third jump, at position 10 + 30 + 30 + 30 = 100
Write an efficient algorithm for the following assumptions:
- X, Y and D are integers within the range [1..1,000,000,000];
- X ≤ Y.
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Solution
Programming language used Java 8
Time spent on task 3 minutes
Notes
not defined yet
Code: 13:40:50 UTC,
java,
autosave
Analysis
Compile error
Solution.java:5: error: incompatible types: possible lossy conversion from double to int
return (Y - X) / D + 0.5;
^
1 error
Analysis
Compile error
Solution.java:5: error: incompatible types: possible lossy conversion from double to int
return (double)((Y - X) / D) + 0.5;
^
1 error
Analysis
Compile error
Solution.java:5: error: incompatible types: possible lossy conversion from double to int
return (Y - X) / (double) D + 0.5;
^
1 error
Analysis
Compile error
Solution.java:5: error: incompatible types: possible lossy conversion from double to int
return (int) (Y - X) / (double) D + 0.5;
^
1 error
Analysis
Analysis
expand all
Example tests
1.
0.004 s
WRONG ANSWER,
got 2 expected 3
Analysis
expand all
Example tests
1.
0.004 s
WRONG ANSWER,
got 2 expected 3
Analysis
expand all
Example tests
1.
0.004 s
WRONG ANSWER,
got 2 expected 3
stdout:
2.5
Analysis
Compile error
Solution.java:5: error: ';' expected
return (int) Math.ceil((Y - X) / (double) D));
^
1 error
Analysis
Analysis
Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(1)
expand all
Correctness tests
1.
0.004 s
OK
2.
0.004 s
OK
1.
0.008 s
OK
2.
0.004 s
OK
1.
0.008 s
OK
2.
0.004 s
OK
1.
0.004 s
OK