Блог пользователя MRs_369

Probably, the solution is executed with error 'uninitialized value usage' on the line 38
Автор MRs_369, история, 4 года назад, По-английски

Hi guys, what did that mean " Probably, the solution is executed with error 'uninitialized value usage' on the line 38 " ?

and thank's in advance

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4 года назад, # |
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Let's say you've declared an integer n that denotes the number of elements to be input. In C/C++, if you don't initialise your variables (manually or through input), they're likely going to contain some junk value, say -431094 or whatever that was present there previously. Now, imagine what happens if you try to declare a vector of size n. Boom. There are various places where this might cause an issue but I'm not going to mention all of the ones I know.

In your case, which I found in your submissions, xx and yy are uninitialized to begin with. So, when you do an equality check, CF tools detect this and flag it as RTE.

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    4 года назад, # ^ |
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    include <bits/stdc++.h>

    using namespace std;

    int main() { int n,a[n+1]; // Probably, the solution is executed with error 'uninitialized value usage' on the line scanf("%d", &n);

    for(int i=0; i<n; i++) {
     scanf("%d", &a[i]);
}
sort(a,a+n);

long long moves = 0;

for(int i=1; i<=n; i++) {
    moves += abs(a[i]-i);
}

printf("%I64d", moves);

return 0;

    }

    Why can't I declare a[n+1]. Please reply, thanks in advance!

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      4 года назад, # ^ |
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      1) That syntax is not part of C++, it's work only as GCC extension;
      2) What do you mean by "can't declare"? You getting some compilation error or what? With extension you can declare array that way;
      3) In your code (seriously plz use some formatting in comments — it's horrible to read) problem is you use variable $$$a[n]$$$ which you never read.

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