Tasks Details
easy
Find value that occurs in odd number of elements.
Task Score
100%
Correctness
100%
Performance
100%
A non-empty array A consisting of N integers is given. The array contains an odd number of elements, and each element of the array can be paired with another element that has the same value, except for one element that is left unpaired.
For example, in array A such that:
A[0] = 9 A[1] = 3 A[2] = 9 A[3] = 3 A[4] = 9 A[5] = 7 A[6] = 9
- the elements at indexes 0 and 2 have value 9,
- the elements at indexes 1 and 3 have value 3,
- the elements at indexes 4 and 6 have value 9,
- the element at index 5 has value 7 and is unpaired.
Write a function:
function solution($A);
that, given an array A consisting of N integers fulfilling the above conditions, returns the value of the unpaired element.
For example, given array A such that:
A[0] = 9 A[1] = 3 A[2] = 9 A[3] = 3 A[4] = 9 A[5] = 7 A[6] = 9the function should return 7, as explained in the example above.
Write an efficient algorithm for the following assumptions:
- N is an odd integer within the range [1..1,000,000];
- each element of array A is an integer within the range [1..1,000,000,000];
- all but one of the values in A occur an even number of times.
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Solution
Programming language used PHP
Total time used 4 minutes
Effective time used 4 minutes
Notes
not defined yet
Task timeline
Code: 12:02:19 UTC,
php,
verify,
result: Failed
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$fil = [];
foreach( $A as $e ) {
if( ! isset( $fil[$i] ) ) {
$fil[$i] = 0;
}
$fil[$i] = $fil[$i] + 1;
}
foreach( $fil as $k => $v ) {
if( $v % 2 !== 0 ) {
return $k;
}
}
}
Analysis
expand all
Example tests
1.
0.026 s
RUNTIME ERROR,
tested program terminated unexpectedly
stderr:
PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 10 Notice: Undefined variable: i in func.php on line 10 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in /tmp/user.php on
Code: 12:02:36 UTC,
php,
verify,
result: Failed
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$fil = [];
foreach( $A as $e ) {
if( ! isset( $fil[$i] ) ) {
$fil[$e] = 0;
}
$fil[$i] = $fil[$i] + 1;
}
foreach( $fil as $k => $v ) {
if( $v % 2 !== 0 ) {
return $k;
}
}
}
Analysis
expand all
Example tests
1.
0.024 s
RUNTIME ERROR,
tested program terminated unexpectedly
stderr:
PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined index: in func.php on line 12 Notice: Undefined index: in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 9 Notice: Undefined variable: i in func.php on line 9
Code: 12:02:44 UTC,
php,
verify,
result: Failed
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$fil = [];
foreach( $A as $e ) {
if( ! isset( $fil[$e] ) ) {
$fil[$e] = 0;
}
$fil[$i] = $fil[$i] + 1;
}
foreach( $fil as $k => $v ) {
if( $v % 2 !== 0 ) {
return $k;
}
}
}
Analysis
expand all
Example tests
1.
0.023 s
RUNTIME ERROR,
tested program terminated unexpectedly
stderr:
PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined index: in func.php on line 12 Notice: Undefined index: in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 PHP Notice: Undefined variable: i in func.php on line 12 Notice: Undefined variable: i in func.php on line 12 Invalid result type, int expected.
Code: 12:02:59 UTC,
php,
verify,
result: Passed
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$fil = [];
foreach( $A as $i ) {
if( ! isset( $fil[$i] ) ) {
$fil[$i] = 0;
}
$fil[$i] = $fil[$i] + 1;
}
foreach( $fil as $k => $v ) {
if( $v % 2 !== 0 ) {
return $k;
}
}
}
Analysis
Code: 12:03:17 UTC,
php,
verify,
result: Passed
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$fil = [];
foreach( $A as $i ) {
if( ! isset( $fil[$i] ) ) {
$fil[$i] = 0;
}
$fil[$i] = $fil[$i] + 1;
}
foreach( $fil as $k => $v ) {
if( $v % 2 !== 0 ) {
return $k;
}
}
return -1;
}
Analysis
Code: 12:03:26 UTC,
php,
verify,
result: Passed
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$fil = [];
foreach( $A as $i ) {
if( ! isset( $fil[$i] ) ) {
$fil[$i] = 0;
}
$fil[$i] = $fil[$i] + 1;
}
foreach( $fil as $k => $v ) {
if( $v % 2 !== 0 ) {
return $k;
}
}
return -1;
}
Analysis
Code: 12:03:29 UTC,
php,
final,
score:
100
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$fil = [];
foreach( $A as $i ) {
if( ! isset( $fil[$i] ) ) {
$fil[$i] = 0;
}
$fil[$i] = $fil[$i] + 1;
}
foreach( $fil as $k => $v ) {
if( $v % 2 !== 0 ) {
return $k;
}
}
return -1;
}Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(N) or O(N*log(N))