原稿 - 英語 - Each time the loop is run i decreases by one. The...

Each time the loop is run i decreases by one. The script between the curly braces of the for loop is run until i is less than 0.

Each time the for loop is run a letter gets added onto the rvsString string. It adds the character from the input text at the index of i. In the string ‘Hello’, H is at the index 0, e is 1, o is 4. Since i starts as the number equal to the index of the last letter, the letters get added in rvsString backwards.