#include <iostream> #include <unordered_map> #include <vector> #include <algorithm> using namespace std; typedef pair<long long,long long> pll; long long checkio(const vector<pll> &v){ long long result=0; long long l,r; vector<pll> se; for(auto &e:v){ l=e.first,r=e.second; auto right=lower_bound(se.begin(),se.end(),make_pair(l,0LL)); //l <= se[right_idx].first size_t right_idx=right-se.begin(); if(right_idx!=0){ size_t left_idx=right_idx-1; if(l<=se[left_idx].second+1){ // overlap with left l=se[left_idx].first; r=max(r,se[left_idx].second); result-=se[left_idx].second-se[left_idx].first+1; se.erase(se.begin()+left_idx); right_idx--; } } while(right_idx<se.size() && se[right_idx].first<=r){ // overlap with right r=max(r,se[right_idx].second); result-=se[right_idx].second-se[right_idx].first+1; se.erase(se.begin()+right_idx); } result+=r-l+1; se.insert(se.begin()+right_idx,make_pair(l,r)); } return result; } int main(){ unordered_map<long long,vector<pll>> dic; long long n,d,t,x,m; scanf("%lld%lld%lld",&n,&d,&t); for(int i=0;i<n;i++){ scanf("%lld",&x); m=(x%d+d)%d; dic[m].emplace_back((x-m)/d-t,(x-m)/d+t); } x=0; for(auto &e:dic)x+=checkio(e.second); printf("%lld\n",x); }