Training ticket


Session
ID: trainingX9C3TGGXZ
Time limit: 120 min.

Status: closed
Created on:
20160421 20:51 UTC
Started on:
20160421 20:51 UTC
Finished on:
20160421 20:51 UTC


Tasks in test  Correctness  Performance  Task score  

1
MinAvgTwoSlice
Submitted in: PHP



100%

A nonempty zeroindexed array A consisting of N integers is given. A pair of integers (P, Q), such that 0 ≤ P < Q < N, is called a slice of array A (notice that the slice contains at least two elements). The average of a slice (P, Q) is the sum of A[P] + A[P + 1] + ... + A[Q] divided by the length of the slice. To be precise, the average equals (A[P] + A[P + 1] + ... + A[Q]) / (Q − P + 1).
For example, array A such that:
A[0] = 4 A[1] = 2 A[2] = 2 A[3] = 5 A[4] = 1 A[5] = 5 A[6] = 8contains the following example slices:
 slice (1, 2), whose average is (2 + 2) / 2 = 2;
 slice (3, 4), whose average is (5 + 1) / 2 = 3;
 slice (1, 4), whose average is (2 + 2 + 5 + 1) / 4 = 2.5.
The goal is to find the starting position of a slice whose average is minimal.
Write a function:
function solution($A);
that, given a nonempty zeroindexed array A consisting of N integers, returns the starting position of the slice with the minimal average. If there is more than one slice with a minimal average, you should return the smallest starting position of such a slice.
For example, given array A such that:
A[0] = 4 A[1] = 2 A[2] = 2 A[3] = 5 A[4] = 1 A[5] = 5 A[6] = 8the function should return 1, as explained above.
Assume that:
 N is an integer within the range [2..100,000];
 each element of array A is an integer within the range [−10,000..10,000].
Complexity:
 expected worstcase time complexity is O(N);
 expected worstcase space complexity is O(N), beyond input storage (not counting the storage required for input arguments).
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$min_avg = ( $A[0] + $A[1] ) / 2;
$index = 0;
$n = count( $A );
$nm = $n  1;
for( $k = 0; $k < $nm; $k++) {
$a = ( $A[$k] + $A[$k+1] ) / 2;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
if( isset( $A[k+3] ) ) {
$a = ( $A[$k] + $A[$k+1] + $A[$k+2] ) / 3;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
}
}
$last = ( $A[$n1] + $A[$n2] ) / 2;
if( $last < $min_avg ) {
$index = $nm1;
}
return $index;
}
PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Undefined offset: 7 in /tmp/user.php on line 21 Notice: Undefined offset: 7 in /tmp/user.php on line 21
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$min_avg = ( $A[0] + $A[1] ) / 2;
$index = 0;
$n = count( $A );
$nm = $n  1;
for( $k = 0; $k < $nm; $k++) {
$a = ( $A[$k] + $A[$k+1] ) / 2;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
if( isset( $A[k+2] ) ) {
$a = ( $A[$k] + $A[$k+1] + $A[$k+2] ) / 3;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
}
}
$last = ( $A[$n1] + $A[$n2] ) / 2;
if( $last < $min_avg ) {
$index = $nm1;
}
return $index;
}
PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 Notice: Use of undefined constant k  assumed 'k' in /tmp/user.php on line 20 PHP Notice: Undefined offset: 7 in /tmp/user.php on line 21 Notice: Undefined offset: 7 in /tmp/user.php on line 21
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$min_avg = ( $A[0] + $A[1] ) / 2;
$index = 0;
$n = count( $A );
$nm = $n  1;
for( $k = 0; $k < $nm; $k++) {
$a = ( $A[$k] + $A[$k+1] ) / 2;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
if( isset( $A[$k+2] ) ) {
$a = ( $A[$k] + $A[$k+1] + $A[$k+2] ) / 3;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
}
}
$last = ( $A[$n1] + $A[$n2] ) / 2;
if( $last < $min_avg ) {
$index = $nm1;
}
return $index;
}
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$min_avg = ( $A[0] + $A[1] ) / 2;
$index = 0;
$n = count( $A );
$nm = $n  1;
for( $k = 0; $k < $nm; $k++) {
$a = ( $A[$k] + $A[$k+1] ) / 2;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
if( isset( $A[$k+2] ) ) {
$a = ( $A[$k] + $A[$k+1] + $A[$k+2] ) / 3;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
}
}
$last = ( $A[$n1] + $A[$n2] ) / 2;
if( $last < $min_avg ) {
$index = $nm1;
}
return $index;
}
// you can write to stdout for debugging purposes, e.g.
// print "this is a debug message\n";
function solution($A) {
// write your code in PHP5.5
$min_avg = ( $A[0] + $A[1] ) / 2;
$index = 0;
$n = count( $A );
$nm = $n  1;
for( $k = 0; $k < $nm; $k++) {
$a = ( $A[$k] + $A[$k+1] ) / 2;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
if( isset( $A[$k+2] ) ) {
$a = ( $A[$k] + $A[$k+1] + $A[$k+2] ) / 3;
if( $a < $min_avg ) {
$index = $k;
$min_avg = $a;
}
}
}
$last = ( $A[$n1] + $A[$n2] ) / 2;
if( $last < $min_avg ) {
$index = $nm1;
}
return $index;
}
The solution obtained perfect score.
https://codility.com/demo/takesampletest/min_avg_two_slice/