#include <iostream> using namespace std; void prime(long long n) { if(!(n%2 == 0 || n%3 == 0 || n%5 == 0 || n%7 == 0) ) { cout<<n<<"\n"; } }; int main() { int a=0,b; cin>>a; long long q[a],w[a]; for(b = 0;b<a;b++) { cin>>q[b]>>w[b]; } for(b=0;b<a;b++) { while(q[b]<=w[b]) { if (q[b] == 0) { q[b]++; continue; } if (q[b] == 1) { q[b]++; continue; } if (q[b] == 2) { cout<<q[b]<<"\n"; q[b]++; continue; } if (q[b] == 3) { cout<<q[b]<<"\n"; q[b]++; continue; } if (q[b] == 5) { cout<<q[b]<<"\n"; q[b]++; continue; } if (q[b] == 7) { cout<<q[b]<<"\n"; q[b]++; continue; } prime(q[b]); q[b]++; } cout<<"\n"; } return 0; }
It looks like your prime function is not working correctly for bigger numbers. You check divisibility for 2,3,5 and 7, which is a necessary condition, but not sufficient.