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How to count items in a Go map?
...ed from the now-retired SO documentation:
m := map[string]int{}
len(m) // 0
m["foo"] = 1
len(m) // 1
If a variable points to a nil map, then len returns 0.
var m map[string]int
len(m) // 0
Excerpted from Maps - Counting map elements. The original author was Simone Carletti. Attribution det...
How to iterate object in JavaScript? [duplicate]
... Neuron
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answered Mar 19 '13 at 10:14
kavinkavin
1,70411 gold badge10...
Matplotlib plots: removing axis, legends and white spaces
...
406
I think that the command axis('off') takes care of one of the problems more succinctly than cha...
How do I print the elements of a C++ vector in GDB?
...
80
To view vector std::vector myVector contents, just type in GDB:
(gdb) print myVector
This wil...
Django: Display Choice Value
...
answered Dec 1 '10 at 5:36
jMylesjMyles
9,74466 gold badges3737 silver badges5151 bronze badges
...
Deleting lines from one file which are in another file
...
answered Jan 24 '11 at 9:06
gabuzogabuzo
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...
How can I measure the speed of code written in PHP? [closed]
...
10 Answers
10
Active
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Equivalent of varchar(max) in MySQL?
...the table.
mysql> CREATE TABLE foo ( v VARCHAR(65534) );
ERROR 1118 (42000): Row size too large. The maximum row size for the used table type, not counting BLOBs, is 65535. This includes storage overhead, check the manual. You have to change some columns to TEXT or BLOBs
But if we try decreasi...
Swift equivalent for MIN and MAX macros
... JackJack
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2
...
Which, if any, C++ compilers do tail-recursion optimization?
...s such as:
int bar(int, int);
int foo(int n, int acc) {
return (n == 0) ? acc : bar(n - 1, acc + 2);
}
int bar(int n, int acc) {
return (n == 0) ? acc : foo(n - 1, acc + 1);
}
Letting the compiler do the optimisation is straightforward: Just switch on optimisation for speed:
For MSVC,...