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iOS Objective-C Basics (Retired) Functional Programming in C Control Flow - For Loops

Stephen Hancock
Stephen Hancock
4,888 Points
Posted by Stephen Hancock
Stephen Hancock
4,888 Points

Value of i

I am not sure I understand why 'i' isn't auto incremented the first time before the sum += many [i]. So the out put would just read 'sum is 4' then 'sum is 12' Can someone help me understand why it doesn't auto increment the first time. thanks

Stephen Hancock
Stephen Hancock
4,888 Points
Stephen Hancock
Stephen Hancock
4,888 Points

--- objective c

int main() {

int many[] = { 2, 4, 8};
int sum = 0;
for (int i=0; i < 3; i++) {
sum += many[i];
printf("sum is %d\n", sum);
}

return 0;

}

1 Answer

Kolapalli Sunil Raghu Vamsee
Kolapalli Sunil Raghu Vamsee
Courses Plus Student 5,122 Points

The third parameter is a step and is executed only after the first cycle of the loop. So the first time the code is executing the first two are statements that are run i.e., initialize and then check if the condition is true. The second iteration onwards, check is done and then the step and the rest of code within the braces.

If you would like to take the step first and then the other stuff you can use the while loop.

Stephen Hancock
Stephen Hancock
4,888 Points
Stephen Hancock
Stephen Hancock
4,888 Points

Thank you Kolapalli, that seems to make sense.