Tasks Details
easy
1.
FrogJmp
Count minimal number of jumps from position X to Y.
Task Score
44%
Correctness
100%
Performance
0%
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.
Copyright 2009–2025 by Codility Limited. All Rights Reserved. Unauthorized copying, publication or disclosure prohibited.
Solution
Programming language used Java 8
Time spent on task 4 minutes
Notes
not defined yet
Task timeline
Code: 16:20:48 UTC,
java,
verify,
result: Passed
// you can also use imports, for example:
// import java.util.*;
// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
class Solution {
public int solution(int X, int Y, int D) {
// write your code in Java SE 8
int ret = 0;
while(true) {
if(Y < X) return ret;
else { Y-=D; ret++; }
}
}
}
Analysis
Code: 16:21:20 UTC,
java,
verify,
result: Failed
// you can also use imports, for example:
// import java.util.*;
// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
class Solution {
public int solution(int X, int Y, int D) {
// write your code in Java SE 8
int ret = 0;
while(true) {
if(Y =< X) return ret;
else { Y-=D; ret++; }
}
}
}
Analysis
Compile error
Solution.java:12: error: > expected
if(Y =< X) return ret;
^
Solution.java:12: error: ')' expected
if(Y =< X) return ret;
^
Solution.java:12: error: not a statement
if(Y =< X) return ret;
^
3 errors
Code: 16:21:30 UTC,
java,
verify,
result: Passed
// you can also use imports, for example:
// import java.util.*;
// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
class Solution {
public int solution(int X, int Y, int D) {
// write your code in Java SE 8
int ret = 0;
while(true) {
if(Y <= X) return ret;
else { Y-=D; ret++; }
}
}
}
Analysis
Code: 16:22:12 UTC,
java,
verify,
result: Passed
// you can also use imports, for example:
// import java.util.*;
// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
class Solution {
public int solution(int X, int Y, int D) {
// write your code in Java SE 8
int ret = 0;
while(true) {
if(Y <= X) return ret;
else { Y-=D; ret++; }
}
}
}
User test case 1:
[20, 200, 40]
Analysis
Code: 16:22:35 UTC,
java,
verify,
result: Passed
// you can also use imports, for example:
// import java.util.*;
// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
class Solution {
public int solution(int X, int Y, int D) {
// write your code in Java SE 8
int ret = 0;
while(true) {
if(Y <= X) return ret;
else { Y-=D; ret++; }
}
}
}
User test case 1:
[20, 200, 40]
User test case 2:
[10, 600, 30]
Analysis
Code: 16:22:53 UTC,
java,
verify,
result: Passed
// you can also use imports, for example:
// import java.util.*;
// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
class Solution {
public int solution(int X, int Y, int D) {
// write your code in Java SE 8
int ret = 0;
while(true) {
if(Y <= X) return ret;
else { Y-=D; ret++; }
}
}
}
User test case 1:
[20, 200, 40]
User test case 2:
[10, 600, 30]
Analysis
Code: 16:23:01 UTC,
java,
final,
score:
44
// you can also use imports, for example:
// import java.util.*;
// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
class Solution {
public int solution(int X, int Y, int D) {
// write your code in Java SE 8
int ret = 0;
while(true) {
if(Y <= X) return ret;
else { Y-=D; ret++; }
}
}
}Analysis summary
The following issues have been detected: timeout errors.
For example, for the input (3, 999111321, 7) the solution exceeded the time limit.
Analysis
Detected time complexity:
O(Y-X)
expand all
Correctness tests
1.
1.408 s
OK
2.
1.449 s
OK
1.
1.422 s
OK
2.
1.435 s
OK
1.
1.436 s
OK
2.
1.437 s
OK
1.
1.443 s
OK
expand all
Performance tests
1.
6.971 s
TIMEOUT ERROR,
running time: 6.97 sec., time limit: 2.75 sec.
1.
8.000 s
TIMEOUT ERROR,
running time: >8.00 sec., time limit: 2.80 sec.
1.
6.961 s
TIMEOUT ERROR,
running time: 6.96 sec., time limit: 2.77 sec.
big_extreme_jump
maximal number of jumps
maximal number of jumps
✘
TIMEOUT ERROR
running time: >8.00 sec., time limit: 2.80 sec.
running time: >8.00 sec., time limit: 2.80 sec.
1.
8.000 s
TIMEOUT ERROR,
running time: >8.00 sec., time limit: 2.80 sec.
1.
3.006 s
TIMEOUT ERROR,
running time: 3.01 sec., time limit: 2.81 sec.