Tasks Details
medium
1.
CountDiv
Compute number of integers divisible by k in range [a..b].
Task Score
100%
Correctness
100%
Performance
100%
Write a function:
class Solution { public int solution(int A, int B, int K); }
that, given three integers A, B and K, returns the number of integers within the range [A..B] that are divisible by K, i.e.:
{ i : A ≤ i ≤ B, i mod K = 0 }
For example, for A = 6, B = 11 and K = 2, your function should return 3, because there are three numbers divisible by 2 within the range [6..11], namely 6, 8 and 10.
Write an efficient algorithm for the following assumptions:
- A and B are integers within the range [0..2,000,000,000];
- K is an integer within the range [1..2,000,000,000];
- A ≤ B.
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Solution
Programming language used Java 8
Time spent on task 2 minutes
Notes
not defined yet
Task timeline
Code: 10:14:33 UTC,
java,
verify,
result: Failed
Analysis
expand all
Example tests
1.
1.333 s
WRONG ANSWER,
got 7 expected 3
Code: 10:16:00 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 A, int B, int K) {
return (B==0) ? 1 : B/K + ( (A==0) ? 1 : (-1)*(A-1)/K);
}
}
Analysis
Code: 10:16:07 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 A, int B, int K) {
return (B==0) ? 1 : B/K + ( (A==0) ? 1 : (-1)*(A-1)/K);
}
}
Analysis
Code: 10:16:12 UTC,
java,
final,
score:
100
// 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 A, int B, int K) {
return (B==0) ? 1 : B/K + ( (A==0) ? 1 : (-1)*(A-1)/K);
}
}Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(1)
expand all
Correctness tests
1.
1.329 s
OK
1.
1.344 s
OK
2.
1.330 s
OK
1.
1.323 s
OK
2.
1.332 s
OK
3.
1.342 s
OK
1.
1.346 s
OK
2.
1.340 s
OK
3.
1.341 s
OK
4.
1.338 s
OK
5.
1.330 s
OK
6.
1.338 s
OK
expand all
Performance tests
1.
1.335 s
OK
1.
1.331 s
OK
1.
1.336 s
OK
2.
1.327 s
OK
1.
1.323 s
OK
2.
1.333 s
OK
3.
1.324 s
OK
4.
1.323 s
OK