Shows segmentation

#1

here is my code


i tried to store all the primes in a vector but I am facing some problems I would be grateful if you can solve this thank you

#2

Hello @gurkirat2600,

There are two errors in your code:

  • vector a is empty while you are iterating over it so, specify size while declaring it, like this.

vector a(max_size,0);

  • in Line 9, you need to iterate from 3 to sqrt(max_size)

for(int i=3;i<max_size;i+=2) change it to
for(int i=3;i*i<max_size;i+=2)

#3

i made the suggested changes but the code fails at test case 3 and also explain why to initilize the vector

#4

@gurkirat2600,

500000th prime = 7,368,787 but your max_size is 500005;
So, increase the limit of the max_size variable.

#5

@gurkirat2600,

You need to iterate over a vector a from 0 to max_size, but a[i] doesn’t exist as a is initially empty with no elements in it and it might give an error (trying to access a memory that never existed).
So, it is necessary to initialize the vector with a specific size (in your case max_size).

#6

thank you for clearing the doubt

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#7

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