k乗をmで割った余りを求めるiPhoneアプリ(C++)のサンプルコードを描いてみます。
#import “ViewController.h”
#include <memory>
using namespace std;
class PowmodCalculator {
public:
int powmod(int, int, int);
private:
void notify(int, int, int);
void notifyAns(int);
};
int PowmodCalculator::powmod(int a, int k, int m) {
notify(a, k, m); // for uiview
if (k == 0)
return 1;
long t = powmod(a, k / 2, m);
t = (t * t) % m;
if (k % 2 == 1)
t = (t * a) % m;
notifyAns((int)t);
return (int)t;
}
void PowmodCalculator::notify(int a, int k, int m) {
[[NSNotificationCenter defaultCenter] postNotificationName:@”my message” object:@[@(a), @(k), @(m)]];
}
void PowmodCalculator::notifyAns(int t) {
[[NSNotificationCenter defaultCenter] postNotificationName:@”my answer” object:@(t)];
}
@interface ViewController ()
@property (nonatomic) int counter;
@property (nonatomic) int answer;
@property (nonatomic, strong) NSMutableArray *queue;
@property (nonatomic, strong) NSMutableArray *queueAnswer;
@property (nonatomic) uint64_t start;
@property (nonatomic) shared_ptr<PowmodCalculator> cppClass;
@end
@implementation ViewController
– (void)viewDidLoad {
[super viewDidLoad];
self.view.backgroundColor = [UIColor colorWithHue:0.25 saturation:0.5 brightness:0.5 alpha:1];
shared_ptr<PowmodCalculator> cppClass(new PowmodCalculator);
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(receiveMessage:) name:@”my message” object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(receiveAnswer:) name:@”my answer” object:nil];
}
– (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
self.answer = self.cppClass->powmod(2, 100000, 345);
}
– (void)receiveMessage:(NSNotification *)notify {
if (!self.queue) {
self.queue = [NSMutableArray array];
}
[self.queue addObject:notify.object];
if([notify.object[1] intValue] == 0) {
[self updateLabel];
}
}
– (void)receiveAnswer:(NSNotification *)notify {
if (!self.queueAnswer) {
self.queueAnswer = [NSMutableArray array];
}
[self.queueAnswer addObject:notify.object];
}
– (void)updateLabel {
++self.counter;
if (self.queue.count == 0) {
[self updateAnswer];
return;
}
NSArray *object = self.queue.firstObject;
[self.queue removeObjectAtIndex:0];
UIView *bar = [[UIView alloc] initWithFrame:CGRectMake(CGRectGetMidX(self.view.bounds), 800, 300, 30)];
bar.backgroundColor = [UIColor yellowColor];
bar.layer.borderWidth = 1;
bar.layer.borderColor = [UIColor lightGrayColor].CGColor;
UILabel *a = [[UILabel alloc] initWithFrame:CGRectMake(10, 0, 50, 30)];
a.font = [UIFont systemFontOfSize:30];
a.text = [NSString stringWithFormat:@”%d”, [object[0] intValue]];
[bar addSubview:a];
UILabel *k = [[UILabel alloc] initWithFrame:CGRectMake(50, 0, 80, 20)];
k.font = [UIFont systemFontOfSize:20];
k.text = [NSString stringWithFormat:@”%d”, [object[1] intValue]];
[bar addSubview:k];
UILabel *m = [[UILabel alloc] initWithFrame:CGRectMake(120, 0, 120, 30)];
m.font = [UIFont systemFontOfSize:30];
m.text = [NSString stringWithFormat:@”%% %d”, [object[2] intValue]];
[bar addSubview:m];
[self.view addSubview:bar];
[UIView animateWithDuration:0.2 animations:^{
bar.center = CGPointMake(CGRectGetMidX(self.view.bounds), CGRectGetMaxY(self.view.bounds) – self.counter * 30 – 80);
}];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.2 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[self updateLabel];
});
}
– (void)updateAnswer {
—self.counter;
if (self.queueAnswer.count == 0) {
return;
}
int object = [self.queueAnswer.firstObject intValue];
[self.queueAnswer removeObjectAtIndex:0];
UILabel *ans = [[UILabel alloc] initWithFrame:CGRectMake(0, –100, 120, 30)];
ans.font = [UIFont systemFontOfSize:30];
ans.text = [NSString stringWithFormat:@”= %d”, object];
[self.view addSubview:ans];
[UIView animateWithDuration:0.2 animations:^{
ans.center = CGPointMake(320, CGRectGetMaxY(self.view.bounds) – self.counter * 30 – 50);
}];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.2 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[self updateAnswer];
});
}
@end