Deepaks prime- getting wrong answer

#1

similiar question was for prateeks candy, here I just increased the maximum value of array to 5000001, but it is accepting only 2 cases, can anybody help?

#include<bits/stdc++.h>
using namespace std;

int a[5000001]={0};
int prime[5000001];
void sieve(){
a[0]=0;
a[1]=0;
a[2]=1;
for(int i=3;ii<=5000001;i+=2){
a[i]=1;
}
for(int i=3;ii<=5000001;i+=2){
if(a[i]){
for(int j=ii;j<=5000001;j+=2i){
a[j]=0;
}
}
}
int count=0;
for(int i=0;i<=5000001;i++){
if(a[i]){
prime[count]=i;
count++;
}
}
}
int main() {
sieve();
int index;
cin>>index;
cout<<prime[index-1]<<endl;
return 0;
}

#2

@Himanish hey himanish this question is application of sieve of eratosthenes. So please apply prime sieve
here otherwise you will get time limit exceed error

#3

I have applied optimised sieve in this question!

#4

@Himanish hey himanish go and watch video of “optimization of sieve of eratosthenes” in your course content you will get idea how to apply prime sieve correctly in optimize ways

#5

sir , same code was uploaded for prateek’s candy which needed optimised sieve, this has the same concept, still WA that is why I am asking.