func_code_string: #include <bits/stdc++.h>   using namespace std;   long long dev[5000005];   long long S[5000005];   long long pri[5000005];   void sieve() {     memset(dev, -1, sizeof dev);     int p = 0;     for (int i = 2; i <= 5000005; i++) {       if (dev[i] != -1) continue;       pri[p++] = i;       for (long long j = 1; j < 5000005; j++) {         if (i * j >= 5000005) break;         dev[i * j] = i;       }     }   }   int main() {     sieve();     for (int i = 1; i < 5000005; i++) {       int x = i;       while (x > 1) {         int d = dev[x];         S[i]++;         x /= d;       }     }     for (int i = 2; i <= 5000005; i++) {       S[i] += S[i - 1];     }     int t;     cin >> t;     while (t--) {       int a, b;       scanf( %d%d , &a, &b);       printf( %I64d n , S[a] - S[b]);     }     return 0;   }   