Codeforces 691F Couple Cover violence

Analysis: Open an array of 300w, statistics, and then NLOGN statistics for each value in order to the first occurrence of the number of cases

Time complexity: O (NLOGN) n at 3e6 order of magnitude

#include <cstdio>#include<cstdlib>#include<cstring>#include<cmath>#include<iostream>#include<algorithm>using namespaceStd;typedefLong LongLL;Const intN =3e6;ConstLL mod = 1e9+7; LL N,m,sum[n+5],c[n+5];intMain () {scanf ("%i64d",&N); intmx=0;  for(intI=1; i<=n;++i) {    intX;SCANF ("%d", &x); + +C[x]; MX=Max (X,MX); }   for(intI=1; i<=mx;++i) {     for(intj=1; j<=mx;++j) {       if(1ll*i*j>n) Break; if(i==j) sum[i*j]+=c[i]* (c[i]-1); Elsesum[i*j]+=c[i]*C[j]; }  }   for(intI=1; i<=n;++i) sum[i]+=sum[i-1]; scanf ("%i64d",&m);  while(m--){    intp; scanf ("%d",&p); printf ("%i64d\n", N (n1)-sum[p-1]); }  return 0;}

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Codeforces 691F Couple Cover violence