A big cat nest, void cat

With 0422

voidcat

As human beings, we have reached a consensus that people will not cherish what they have already got (including all materials or feelings) in most cases, unless it is a new one.

Also, people will never learn a lesson. Ironically, the only lesson learned is that human beings will never learn this lesson.

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Why can't the speed of light be exceeded

voidcat

The basic assumption of this theory, called relativity, is that no matter the observers move freely at any speed, the laws of science should be the same for them. This is certainly true for Newton's law of motion, but now this concept has been extended to include Maxwell's theory and the speed of light: no matter how fast observers move, they should measure the same speed of light. This simple idea has some extraordinary conclusions. Perhaps the most famous is the equivalence of mass and energy, which can be expressed by Einstein's famous equation E=mc2 (E is energy, m is mass, c is the speed of light), and the law that nothing can travel faster than light. Due to the equivalence of energy and mass, the energy of an object due to its motion should be added to its mass. In other words, it will be more difficult to accelerate it. This effect has practical significance only when the object moves at a speed close to the speed of light. For example, the mass of an object moving at 10% speed of light is only 0.5% higher than the original, while the mass of an object moving at 90% speed of light becomes more than twice the normal mass. When an object approaches the speed of light, its mass rises faster and faster, so it needs more and more energy to accelerate further. In fact, it can never reach the speed of light, because then the mass will become infinite, and according to the principle of mass energy equivalence, this requires infinite energy to do. For this reason, relativity limits the speed of motion of objects: any normal object always moves at a speed lower than the speed of light, and only light or other waves without intrinsic mass can travel at the speed of light

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Which operations of MySQL will be recorded to the Binlog file

voidcat

Statement In the mode, all successful DDL and DML operations will be recorded, including UPDATE and DELETE The operation affects the case where the number of rows is 0.

Row In the mode, all DDL and DML operations that are executed successfully and return more than 0 rows of influence will be recorded. When UPDATE and DELETE When the number of rows affected by the operation is 0, the operation will not be recorded to Binlog.

Mixed In the mode, when an SQL analysis shows that it should use Statement When writing Binlog in the mode, follow the Statement Rule, when an SQL analysis indicates that it should use Row When writing Binlog in the mode, follow the Row Rules.

An UPDATE contains a USER() function, and the number of affected rows returned by the operation is 0 when the operation succeeds. Since the SQL contains a USER() function, the Row Rule, so this will not be recorded in Binlog.
One SQL UPDATE SET NAME = 'kd' WHERE ID = 1 , and the data with ID 1 does not exist. Although the execution is successful and the number of returned affected rows is 0, this SQL will use Statement Therefore, this operation will still be recorded in Binlog.

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IOS border gradient+rounded corner

voidcat

 self.bottomView.backgroundColor = [UIColor colorWithWhite:1 alpha:0.1]; CAGradientLayer *gradientLayer = [CAGradientLayer layer]; gradientLayer.frame = self.bottomView.bounds; gradientLayer.colors = @[(id)[UIColor colorWithHexString:@"#CD66FD"]. CGColor, (id)[UIColor colorWithHexString:@"#05DFF8"]. CGColor]; CAShapeLayer *maskLayer = [CAShapeLayer layer]; maskLayer.lineWidth = 1.0; maskLayer.path = [UIBezierPath bezierPathWithRoundedRect:self.bottomView.bounds cornerRadius:6.0]. CGPath; //    maskLayer.path = [UIBezierPath bezierPathWithRect:self.bottomView.bounds]. CGPath; maskLayer.fillColor = [UIColor clearColor]. CGColor; maskLayer.strokeColor = [UIColor blackColor]. CGColor; maskLayer.cornerRadius = 6.0; //  Add Rounds gradientLayer.mask = maskLayer; [self.bottomView.layer addSublayer:gradientLayer];

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IOS overlay view

voidcat

Similar effect

 // //  AvatarListView.h //  UniversalApp // //  Created by voidcat on 2024/4/13. //  Copyright  ©  2024 voidcat.  All rights reserved. // #import <UIKit/UIKit.h> NS_ASSUME_NONNULL_BEGIN //Head portrait view class @interface AvatarView : UIView @property (nonatomic, strong) UIImageView *avatarImageView; @property (nonatomic, assign) CGFloat overlappingOffset; - (instancetype)initWithImage:(UIImage *)image; @end @interface AvatarListView : UIView - (void)addAvatarWithImage:(UIImage *)image; - (void)removeLastAvatar; @end NS_ASSUME_NONNULL_END

 #import "AvatarListView.h" //Implementation of avatar view class @implementation AvatarView - (instancetype)initWithImage:(UIImage *)image { self = [super initWithFrame:CGRectMake(0, 0, 50, 50)]; if (self) { _avatarImageView = [[UIImageView alloc] initWithImage:image]; _avatarImageView.frame = self.bounds; _avatarImageView.layer.cornerRadius = self.frame.size.width / 2; _avatarImageView.clipsToBounds = YES; [self addSubview:_avatarImageView]; _overlappingOffset = 10.0f; } return self; } @end @interface AvatarListView () @property (nonatomic, strong) NSMutableArray<AvatarView *> *avatarViews; @property (nonatomic, assign) CGFloat overlappingOffset; @end @implementation AvatarListView - (instancetype)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; if (self) { _avatarViews = [NSMutableArray array]; _overlappingOffset = 10.0f; } return self; } - (void)addAvatarWithImage:(UIImage *)image { AvatarView *avatarView = [[AvatarView alloc] initWithImage:image]; [self addSubview:avatarView]; CGFloat x = 0; if (_avatarViews.count > 0) { x = _avatarViews.lastObject.frame.origin.x + _avatarViews.lastObject.frame.size.width - _overlappingOffset; } avatarView.frame = CGRectMake(x, 0, 50, 50); [_avatarViews addObject:avatarView]; } - (void)removeLastAvatar { if (_avatarViews.count > 0) { AvatarView *lastAvatar = _avatarViews.lastObject; [lastAvatar removeFromSuperview]; [_avatarViews removeLastObject]; } } @end

use

 AvatarListView *avatarListView = [[AvatarListView alloc] initWithFrame:CGRectMake(20, 100, 300, 50)]; [self addSubview:avatarListView]; [avatarListView addAvatarWithImage: [UIImage imageName: @ "default avatar"]]; [avatarListView addAvatarWithImage: [UIImage imageName: @ "default avatar"]]; [avatarListView addAvatarWithImage: [UIImage imageName: @ "default avatar"]];

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IOS gradient and fillet coexist

voidcat

Fillet radian Under the same condition

 //Create CAGradientLayer CAGradientLayer *gradientLayer = [CAGradientLayer layer]; //Set Gradient gradientLayer.colors = @[(__bridge id)[UIColor colorWithRed:77.0/255.0 green:144.0/255.0 blue:255.0/255.0 alpha:1.0]. CGColor, (__bridge id)[UIColor colorWithRed:206.0/255.0 green:100.0/255.0 blue:255.0/255.0 alpha:1.0]. CGColor]; //Set Gradient Direction gradientLayer.startPoint = CGPointMake(0.0, 0.5); gradientLayer.endPoint = CGPointMake(1.0, 0.5); //Set frame gradientLayer.frame = self.orderBg.bounds; //Create a Bezier path for drawing fillets UIBezierPath *roundedRectPath = [UIBezierPath bezierPathWithRoundedRect:gradientLayer.bounds  byRoundingCorners:UIRectCornerAllCorners cornerRadii:CGSizeMake(30.0, 10.0)]; //Create a shape layer as the mask of the gradientLayer CAShapeLayer *maskLayer = [CAShapeLayer layer]; maskLayer.path = roundedRectPath. CGPath; //Assign the maskLayer to the mask of the gradientLayer gradientLayer.mask = maskLayer; //Add gradient to our view [self.orderBg.layer insertSublayer:gradientLayer atIndex:0];

When the fillet radians are different

 //Create CAGradientLayer CAGradientLayer *gradientLayer = [CAGradientLayer layer]; //Set Gradient gradientLayer.colors = @[(__bridge id)[UIColor colorWithRed:77.0/255.0 green:144.0/255.0 blue:255.0/255.0 alpha:1.0]. CGColor, (__bridge id)[UIColor colorWithRed:206.0/255.0 green:100.0/255.0 blue:255.0/255.0 alpha:1.0]. CGColor]; //Set Gradient Direction gradientLayer.startPoint = CGPointMake(0.0, 0.5); gradientLayer.endPoint = CGPointMake(1.0, 0.5); //Set frame gradientLayer.frame = self.orderBg.bounds; //Create a Bezier path for drawing fillets UIBezierPath *roundedRectPath = [UIBezierPath bezierPathWithRoundedRect:gradientLayer.bounds  byRoundingCorners:UIRectCornerAllCorners cornerRadii:CGSizeMake(30.0, 10.0)]; //Create a shape layer as the mask of the gradientLayer CAShapeLayer *maskLayer = [CAShapeLayer layer]; maskLayer.path = roundedRectPath. CGPath; //Assign the maskLayer to the mask of the gradientLayer gradientLayer.mask = maskLayer; //Add gradient to our view [self.orderBg.layer insertSublayer:gradientLayer atIndex:0];

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Whether the tyrant is free

voidcat

First, remember that there are similarities between city-state and individual personality, and then observe the personality characteristics of each city-state and individual one by one

A country ruled by tyrants. Do you think it is free or enslaved?

Therefore, if an individual is like a country, he must have the same situation. His mind is full of slavery and non freedom, and his best and most rational part is enslaved; A small part, the most vicious and violent part, plays the role of tyrant. isn't it?

Therefore, the mind that practices the tyrant system - the mind as a whole - is also the least able to do what it wants to do. Because it is always driven by crazy desire, it is full of chaos and regret.

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Why people like democracy

voidcat

In the eyes of wise people like Socrates, democracy is just a group of ragtag people coming together to solve problems. Most people's opinions are not necessarily right, and truth is often in the hands of a few elites.

We said that unless a person with high talent plays and learns in a good environment from an early age and is well educated, he cannot grow into a good person. The democratic system tramples on all these ideals in a frivolous attitude, without asking a person what he used to do or what his character was. As long as he claims to be good to the people when he turns to politics, he will be respected and honored.

I imagine that he will spend money, time and hard work on unnecessary desires as much as he spends on necessary desires in the rest of his life. If he is lucky enough to take the initiative for a short time, his spirit will become more stable as he gets older, and some of the exiled elements will return successively, and the invaders will be restrained. He will establish equality among all kinds of happiness. When he completely controls the next happiness, he will let that happiness be satisfied. Then he will take turns, with equal opportunities, and all kinds of happiness will be satisfied.

If someone told him that some happiness comes from noble good desires, which should be encouraged and satisfied, and some happiness comes from inferior bad desires, which should be controlled and suppressed, he would ignore this and would not open the gate of the fortress to the truth. He would shake his head and say that all happiness is equal and should be respected equally.

In fact, he indulged in his turn of happiness day by day. Today is drinking, women, singing, and tomorrow drinking water, into the strict diet; The first day is intense physical exercise, and the second day is idle, lazy and neglectful; Then for a while, he began to study philosophy. He often wants to engage in politics. He often jumps up and says whatever comes to his mind. Sometimes, he is ambitious, and all his efforts are focused on the military. Sometimes, he is concentrated on doing business and getting rich. His life is out of order and temperance. He thinks his way of life is happy, free and happy, and he will stick to it to the end

I believe that this kind of person is the most diverse person who gathers the most habits in one body, just as that kind of democratic city-state has multifaceted complexity. This kind of person is also colorful, gorgeous, envied by many men and women, and contains the most systems and life patterns.

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along with

voidcat

This is not the beginning, nor the end. It will not end.

Greed is disgusting and disappointing.

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Debate on young people

voidcat

When young people began to try to argue, they liked to argue with others everywhere because they thought it was fun. They imitated the refutation of others and refuted others themselves. They like to use words to bite people just as dogs like to drag and bite all people who come near.

When they refute others many times, and they are refuted by others many times, they soon fall into a strong doubt about what they thought was right.

But an older person would not be so crazy. He would rather follow the example of those who argue for the truth, rather than those who just play to whet their tongues. So he will be a prudent person

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