C program : crashes for values greater than 0.3 million [duplicate] - c

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Big array gives segmentation error in C
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This program is to find the prime number which is is the sum of most number of consecutive prime numbers. When I set the value of LIMIT to 50 100 or even 1000, the correct values are obtained. But if I take the value of LIMIT greater than 0.3 million the program crashes. What is the reason behind this problem and how can I solve it?
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
#define LIMIT 300000
//binary search function
int Bsearch(long long int *arr,long long int low,long long int high,long long int search)
{
if(high<low)
return 0;
long long int mid = (low+high)/2;
if(search<arr[mid])
{return(Bsearch(arr,low,mid-1,search));}
else if(search>arr[mid])
{return(Bsearch(arr,mid+1,high,search));}
else if(search==arr[mid]) return 1;
else return 0;
}
int main()
{
long int arr[LIMIT];
arr[0]=0;arr[1]=1;
for(long long int i=2;i<=LIMIT;i++)
{arr[i]=1;}
long long index=2;
for(long long int i=3;i<=LIMIT;i++,index++)
{
for(long long int j=2;j<=sqrt(i);j++)
{
if(i%j==0)
{arr[index]=0;}
}
}
long long int count=0;
//calculate total primes
for(long int A=0;A<LIMIT;A++)
{
if(arr[A]==1)
count++;
}
//all primes stored in seperate primes array
long long int primes[count];
for(long int A=0,index=0;A<LIMIT;A++)
{
if(arr[A]==1)
{
primes[index++]=A+1;
}
}
long long int primes_sum[count];
primes_sum[0]=primes[0];
for(long long int B=1;B<count;B++)
{primes_sum[B]=primes_sum[B-1]+primes[B];}
for(long long int i =0;i<(sizeof(primes)/sizeof(long long int));i++)
{
printf("\nprime number : %lld\tprimes_sum : %lld",primes[i],primes_sum[i]);
}
struct ultimata
{
long long int num_of_primes;
long long int prime_number;
}final;
final.num_of_primes=0;final.prime_number=0;
for(long long int j=(sizeof(primes_sum)/sizeof(long long int))-1;j>=2;j--)
{
for(long long int i=j-2;i>=1;i--)
{
long long int search_term = primes_sum[j]-primes_sum[i];
printf("\nsearch term : %lld (primes_sum[%lld]-primes_sum[%lld])",search_term,j,i);
if(search_term>LIMIT)
break;
if(Bsearch(primes,0,(sizeof(primes)/sizeof(long long int)),search_term))
{
printf("\nfound! : %lld terms : %lld",search_term,j-i-1);
if((j-i-1)>final.num_of_primes)
{
printf("\nfound! : %lld",search_term);
final.prime_number=search_term;
final.num_of_primes=j-i-1;
}
}
}
}
printf("Largest prime number : %lld",final.prime_number,final.num_of_primes);
return 0;
}

Answer 1

I think one of your problems is in these lines (multiple times in other places, too):
long int arr[LIMIT];
...
for(long long int i=2;i<=LIMIT;i++)
{arr[i]=1;}
Your array has LIMIT entries, but you try to write to entry LIMIT+1. C starts with array index 0 and ends with size-1.
I don't know why it works for smaller values of LIMIT.