This content is archived!
For the 2018-2019 school year, we have switched to using the WLMOJ judge for all MCPT related content. This is an archive of our old website and will not be updated.The following provides an overview of counted loops:
Turing
for i : startValue .. endValue
% code
% code
end for
Python
for iteratingVariable in sequence:
# code
# code
Java
for (initial condition; condition; increment) {
// code
// code
}
The following example will make the use of these loops clearer. Let’s say we wanted to print Hello World!
5 times. We could accomplish this as follows:
Turing
for i : 1 .. 5
put("Hello World!")
end for
Python
for i in range(1, 5):
print("Hello World!")
Java
for (int i = 0; i < 5; i++) {
System.out.println("Hello World!");
}
But, what if we wanted to increment by a number other than one? For example, to output all the multiples of 3 from 1 to 14, we could iterate from 1 to 14 and use conditionals to check for multiplicity. However, we can achieve the same result using loops as follows. (We know that the first number will be 3)
Turing
for i : 3 .. 14 by 3
put i
end for
Python
for i in range(3, 15, 3): # 15 because we want to go to 14 and Python's ranges are closed at the end.
print(i)
Java
for (int i = 3; i <= 14; i += 3){
System.out.println(i);
}
Practice
Use counted loops to output a 5 by 5 times table as follows:
1 | 2 | 3 | 4 | 5 |
2 | 4 | 6 | 8 | 10 |
3 | 6 | 9 | 12 | 15 |
4 | 8 | 12 | 16 | 20 |
5 | 10 | 15 | 20 | 25 |