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Endless use for the cycle continues

I am writing code that will run through every bit in the histogram and check if there are non-zero bins. If so, it issues an error message. My problem is that I want it to skip bin because that bin shouldn't be empty, but check all other cells.

This alone creates an endless loop. Here's my code

Int_t y;

for (int i = 0; i <= 100; i++) {
    y = hist - > GetBinContent(i)

    if (i = 1) continue;
    else if (y != 0) {
        std: cout << * * * * * ERROR * * * * * << std: endl;
        break;
    }

}

What happens is it evaluates it for i = 0

, skips i = 1

it and then deletes it i = 2

and just continually evaluates it over and over. If I choose "if (i = 1) continue;" line then it works.

Any ideas?

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2 answers


try it

if (i==1) continue;


i=1

means you are assigning 1

to i

. =

means assignment and ==

average comparison.

In your code, the value i

will always be 1

as you are usingi=1

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When you have bugs with loops, it sometimes helps to run it in debug mode with a breakpoint in the loop, or put a print expression in it. Your error comes from a string:    if (i=1) continue;

. The segment i=1

sets i to one and returns i, which is interpreted as true (since it is nonzero). It then moves on to the next iteration where it sets the i to one again. Most likely it was if (i==1) continue;

. This does the comparison operator you intended.



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