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How to remove leading and trailing whitespace in a MySQL field?
... only removes spaces - not tabs, formfeeds etc. A combination of TRIMs specifying other whitespace characters may provide a limited improvement e.g. TRIM(BOTH '\r' FROM TRIM(BOTH '\n' FROM TRIM(BOTH '\f' FROM TRIM(BOTH '\t' FROM TRIM(txt))))). But the problem with this approach is only a single char...
design a stack such that getMinimum( ) should be O(1)
.... Note that this doesn't change the complexity of the space required, e.g. if you've got a stack with O(n) space requirements, this will still be O(n) just with a different constant factor.
Non-constant-space solution
Keep a "duplicate" stack of "minimum of all values lower in the stack". When you...
Check variable equality against a list of values
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You could use an array and indexOf:
if ([1,3,12].indexOf(foo) > -1)
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Check Whether a User Exists
...n also check user by id command.
id -u name gives you the id of that user.
if the user doesn't exist, you got command return value ($?)1
And as other answers pointed out: if all you want is just to check if the user exists, use if with id directly, as if already checks for the exit code. There's no ...
if else statement in AngularJS templates
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Angularjs (versions below 1.1.5) does not provide the if/else functionality . Following are a few options to consider for what you want to achieve:
(Jump to the update below (#5) if you are using version 1.1.5 or greater)
1. Ternary operator:
As suggested by @Kirk in the comm...
Shortest distance between a point and a line segment
... const float l2 = length_squared(v, w); // i.e. |w-v|^2 - avoid a sqrt
if (l2 == 0.0) return distance(p, v); // v == w case
// Consider the line extending the segment, parameterized as v + t (w - v).
// We find projection of point p onto the line.
// It falls where t = [(p-v) . (w-v)] /...
How to print binary tree diagram?
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I've created simple binary tree printer. You can use and modify it as you want, but it's not optimized anyway. I think that a lot of things can be improved here ;)
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class BTreePrinterTest {
p...
How to know if two arrays have the same values
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function arraysEqual(_arr1, _arr2) {
if (!Array.isArray(_arr1) || ! Array.isArray(_arr2) || _arr1.length !== _arr2.length)
return false;
var arr1 = _arr1.concat().sort();
var arr2 = _arr2.concat().sort();
for (var i = 0; i < arr1.length; i...
What is the relative performance difference of if/else versus switch statement in Java?
Worrying about my web application's performances, I am wondering which of "if/else" or switch statement is better regarding performance?
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Switch statement for greater-than/less-than
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1.0 time 37ms 73ms 68ms 184ms 73ms 21ms
if-immediate 1.0 1.0 1.0 2.6 1.0 1.0
if-indirect 1.2 1.8 3.3 3.8 2.6 1.0
switch-immediate 2.0 1.1 2.0 1.0 2.8 1.3
switch-range ...