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How to easily initialize a list of Tuples?
...
c# 7.0 lets you do this:
var tupleList = new List<(int, string)>
{
(1, "cow"),
(5, "chickens"),
(1, "airplane")
};
If you don't need a List, but just an array, you can do:
var tupleList = new(int, string)[]
{
(1, "cow"),
(5, "chicke...
Avoiding if statement inside a for loop?
...ex index = 0) {
for (const auto& e : c)
f(index++, e);
}
int main() {
using namespace std;
set<char> s{'b', 'a', 'c'};
// indices starting at 1 instead of 0
for_each_indexed(s, [](size_t i, char e) { cout<<i<<'\t'<<e<<'\n'; }, 1u);
...
How to unit test abstract classes: extend with stubs?
... then you can factor out the helper methods into one class (scenario2) and convert the inheritance tree into a strategy pattern.
If you find you have some methods your base class implements directly and other are virtual, then you can still convert the inheritance tree into a strategy pattern, but...
What are the differences between a pointer variable and a reference variable in C++?
...
A pointer can be re-assigned:
int x = 5;
int y = 6;
int *p;
p = &x;
p = &y;
*p = 10;
assert(x == 5);
assert(y == 10);
A reference cannot, and must be assigned at initialization:
int x = 5;
int y = 6;
int &r = x;
...
How can I declare and define multiple variables in one line using C++?
...
int column = 0, row = 0, index = 0;
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Int division: Why is the result of 1/3 == 0?
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The two operands (1 and 3) are integers, therefore integer arithmetic (division here) is used. Declaring the result variable as double just causes an implicit conversion to occur after division.
Integer division of course returns the true result of divisi...
How do I generate random integers within a specific range in Java?
How do I generate a random int value in a specific range?
66 Answers
66
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datetime dtypes in pandas read_csv
...n has a keyword argument called parse_dates
Using this you can on the fly convert strings, floats or integers into datetimes using the default date_parser (dateutil.parser.parser)
headers = ['col1', 'col2', 'col3', 'col4']
dtypes = {'col1': 'str', 'col2': 'str', 'col3': 'str', 'col4': 'float'}
par...
Explicit specialization in non-namespace scope [duplicate]
...ion:
namespace detail {
template <typename TL> void Verify (int, int[]) {}
template <> void Verify<int>(int, int[]) {}
}
template<typename T> class CConstraint {
// ...
template <typename TL> void Verify(int position, int constraints[]) ...
Macro vs Function in C
...ample, this macro:
#define square(a) a * a
works fine when used with an integer:
square(5) --> 5 * 5 --> 25
but does very strange things when used with expressions:
square(1 + 2) --> 1 + 2 * 1 + 2 --> 1 + 2 + 2 --> 5
square(x++) --> x++ * x++ --> increments x twice
Putt...