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# How to analyze that how much times a loop has been executed? How can we create logic?

15th Aug 2017, 1:46 PM
om Patel
2 ответов
+ 5
Put a logger inside your loop, run the code. The amount of times the logger has printed out == no of times loop ran. Or increment a variable by each time it runs, print the variable when the loop ends.
15th Aug 2017, 1:56 PM
Wen Qin
+ 3
If you have one loop, you can likely figure it out by looking at it. for (int i = 0; i <= 25; i += 2){} i would run 26 times had it of been i++. Since its i += 2, we just divide it by 2. So, it will run 13 times. Maybe it gets tough when you get to something like this: for (int i = 0; i < 15; i++) for (int k = 0; k < 3; k++) for (int w = 0; w < 9; w += 2) {} How can we easily figure out how many times this will run, without debugging? Well, how many times does each loop run individually? The w loop runs 9 / 2 times. = 5 (Rounds up). The k loop runs 3 times The i loop runs 15 times. Now, since an inner loop must finish before the outer loop moves to the next itteration, we can multiply those numbers to get our result: (This is how I would do the multiplication if I have not memorized what 15 * 15 was) 15 * 3 * 5 = 15 * 15 = 150 + (5 * 15) = 150 + (50 + 25) = 225 Those loops will run 225 times. We'll try one more to make sure you get the idea: for(int i = 2; i < 12; i += 5) for (int k = 0; k <= 10; k += 3) {} k loop runs 11 / 3 times = 4 (Rounds up) i loop runs 10 / 5 times = 2 **Note** If the increase to the variable is to large (or small), you may not get an extra itteration. Meaning, sometimes you could have to round down. ** So, 4 * 2 = 8. Those loops run 8 times. The point is there's a mathematical trick to finding out how many times the loop runs.
15th Aug 2017, 2:41 PM
Rrestoring faith