k06a

@interface NSIndexPath (SharedIndexPath)
@end
@implementation NSIndexPath (SharedIndexPath)
+ (instancetype)sharedIndexPathForRow:(NSInteger)row inSection:(NSInteger)section
{
    static NSIndexPath *arr[10][10] = {nil};
    if (arr[row][section] == nil)
        arr[row][section] = [NSIndexPath indexPathForRow:row inSection:section];
    return arr[row][section];
}

k06a

func bind1<T1,V>(f: (T1)->V, t1: T1) -> ()->V
{
    return { () -> V in f(t1) }
}

func bind1<T1,T2,V>(f: (T1,T2)->V, t1: T1) -> (T2)->V
{
    return { t2 -> V in f(t1,t2) }
}

k06a

prefix func !<T>(f: (T)->Bool) -> (T)->Bool
{
    return { !f($0) }
}

func &&<T>(f1: (T)->Bool, f2: (T)->Bool) -> (T)->Bool
{
    return { f1($0) && f2($0) }
}

k06a

func elem<T: Equatable>(item: @autoclosure ()->T) -> (@autoclosure ()->[T]) -> Bool {
    return { (arr: @autoclosure ()->[T]) in find(arr(), item()) != nil }
}

let found = elem (2) ([1,2,3]) // Hope to avoid braces in future

k06a

Before iOS 8, you do this:
```
[backgroundViewController setModalPresentationStyle:UIModalPresentationCurrentContext];
[backgroundViewController presentViewController:_myMoreAppsViewController animated:NO completion:nil];
```
in iOS 8, you have to do this:
```
backgroundViewController.providesPresentationContextTransitionStyle = YES;
backgroundController.definesPresentationContext = YES;
[overlayViewController setModalPresentationStyle:UIModalPresentationOverCurrentContext];

k06a

int64_t nn = 100000000;
vector<int> ip(nn,1);
size_t pos = 2;
ip[0] = 0;
ip[1] = 0;
while ((pos = find(ip.begin()+pos, ip.end(), 1) - ip.begin()) < nn) {
    for (size_t j = pos*pos; j < ip.size(); j+=pos)
        ip[j] = 0;
    pos += 1 + (pos>2);
}

k06a

#import <UIKit/UIKit.h>

@interface TintedButton : UIButton

@end

k06a

#import <Cocoa/Cocoa.h>
#import <objc/runtime.h>

@implementation NSControl (Subclasses)

+ (void)load
{
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        method_exchangeImplementations(class_getInstanceMethod([self class], @selector(initWithCoder:)),

k06a

string add(const string & s1, const string & s2)
{
    int flag = 0;
    string ret(std::max(s1.size(),s2.size())+1, '0');
    for (int i = 0; i < ret.size(); i++) {
        int v = (i < s1.size() ? s1[s1.size()-1-i]-'0' : 0)
              + (i < s2.size() ? s2[s2.size()-1-i]-'0' : 0) + flag;
        flag = v/10;
        v -= flag*10;
        ret[ret.size()-1-i] = v+'0';

k06a

struct RefString
{
    RefString(const string & s, int i, int l) : s(s), i(i), l(l) {}

    const char & operator [] (int x) const {
        return s[i+x];
    }
    
    size_t length() const {
        return l;