Why is subtracting these two times (in 1927) giving a strange result? If I run the following program, which parses two date strings referencing times one second apart and compares them: public static void main(String[] args) throws ParseException { SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); String str3 = "1927-12-31 23:54:07"; String str4 = "1927-12-31 23:54:08"; Date sDt3 = sf.parse(str3); Date sDt4 = sf.parse(str4); long ld3 = sDt3.getTime() /1000; long ld4 = sDt4.getTime() /1000; System.out.println(ld4-ld3); } The output is: 353 Why is ld4-ld3 not 1 (as I would
Why is it faster to process a sorted array than an unsorted array? Here is a piece of C++ code that seems very peculiar. For some strange reason, sorting the data miraculously makes the code almost six times faster. #include <algorithm> #include <ctime> #include <iostream> int main() { // Generate data const unsigned arraySize = 32768; int data[arraySize]; for (unsigned c = 0; c < arraySize; ++c) data[c] = std::rand() % 256; // !!! With this, the next loop runs faster std::sort(data, data