SunXiaoShan

static int getMinPathValue(int[][] input) {

    int[] firstLine = input[0];
    ArrayList<Integer> buff = new ArrayList<Integer>(Collections.nCopies(firstLine.length, Integer.MAX_VALUE));
    int result = 0;

    for (int y=0; y<input.length; y++) {
        for (int x=0; x<input.length; x++) {
            if (input[y][x] < buff.get(x)) {
                buff.set(x, input[y][x]);

SunXiaoShan

const NSTimeInterval INTERVAL_TIME = 0.5; // 0.5 sec
RACSubject *subject = [RACSubject subject];
[[subject throttle:INTERVAL_TIME] subscribeNext:^(id  _Nullable x) {
    NSLog(@"%@",x);
}];
[subject sendNext:@1];
[subject sendNext:@2];
[subject sendNext:@3];
[subject sendNext:@4];

SunXiaoShan

RAC(self.labelView, text) = [RACObserve(objA, strContent) distinctUntilChanged];
objA.strContent = @"content1"; // 1st
objA.strContent = @"content1"; // 2nd
objA.strContent = @"content1"; // 3rd

SunXiaoShan

function main(data,cb){
	fun1(data,function(err,data){
		if(!err){
			fun2(data,function(err,data){
				if(!err){
					fun3(data,cb);
				}else{
					cb(err);
				}
			});

SunXiaoShan

// Define function 
- (RACSignal *)RACSignalDemoA {
    return [RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {
        NSLog(@"handle A");
        [subscriber sendNext:@"A"];
        [subscriber sendCompleted];
        return nil;
    }];
}

SunXiaoShan

- (RACSignal *)RACSignalDemoFunction {
    return [RACSignal createSignal:^(id<RACSubscriber> subscriber) {
        // your code ...
        BOOL isSuccess = YES;
        NSObject *result = [NSObject new];
        if (isSuccess) {
            [subscriber sendNext:result];
            [subscriber sendCompleted];
            
        } else {

SunXiaoShan

// JAVA 
// QUESTION 1
static String getReverseString(String input) {
    char[] in = input.toCharArray();
    char buff;
    for (int i=0,j=input.length()-1; i<input.length()/2;i++,j--) {
        buff = in[i];
        in[i] = in[j];
        in[j] = buff;
    }

SunXiaoShan

@interface Model:NSObject
@property (strong, nonatomic) NSString *content;
@end

@implementation Model
@end

@interface ViewModel:NSObject
@property (strong, nonatomic) NSString *content;
- (void) execute:(NSString *)content;

SunXiaoShan

 [[self.btnButton rac_signalForSelector:@selector(actionButton:)] subscribeNext:^(RACTuple * _Nullable x) {
    NSLog(@"button click..");
}];

SunXiaoShan

[[[NSNotificationCenter defaultCenter] rac_addObserverForName:UIKeyboardDidShowNotification object:nil] subscribeNext:^(NSNotification * _Nullable x) {
    NSLog(@"keyboard - \n%@", x);
}];