Using while / do-while loops for array element setting

Question

I'm having some trouble understanding how to use a while loop to get the same results as this for loop:

for (int i=0; i<N; i++){
    int datum[i] = 0;
}

Basically, to set all the elements in the array datum[N] to 0. Does the following code make sense in that regard, or am I missing something? thanks

int i = 0;
while (i < N){
    datum[i] = 0;
    i++;
}

No you're not :) But for the first loop, why int? You can't redeclare datum[i]. — Rakete1111
– Rakete1111, Commented May 21, 2016 at 14:25
Initialize them to zero with int datum[N] = {0}; would be better practice generally. — Scott Stainton
– Scott Stainton, Commented May 21, 2016 at 14:27
@ScottStainton: int datum[N] = {} makes more logical sense in C++. — Lightness Races in Orbit
– Lightness Races in Orbit, Commented May 21, 2016 at 14:38

sebenalern · Accepted Answer · 2016-05-21 14:36:10Z

3

These two code examples produce the same results.

int i = 0;
while (i < N)
{
     datum[i] = 0;
     i++;
}

for (int i=0; i<N; i++) 
{
   datum[i] = 0; // remove int because you will be redclaring datum
}

answered May 21, 2016 at 14:36

sebenalern

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Comments

Lightness Races in Orbit · Accepted Answer · 2016-05-21 14:39:48Z

2

Don't use either of them. When you declare datum, do so like this:

std::vector<int> datum(N);

Done.

answered May 21, 2016 at 14:39

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