#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
constexpr int N = 5e5;
int a[N+9];
int pref[N+9];
int suf[N+9];
int skad[N+9];
vector<ll> tree[N+9];
vector<ll> lazy[N+9];
vector<ll> dp[N+9];
int base=1;
void daj(int x, int p){
tree[p][2*x]+=lazy[p][x]; tree[p][2*x+1]+=lazy[p][x];
lazy[p][2*x]+=lazy[p][x]; lazy[p][2*x+1]+=lazy[p][x];
lazy[p][x]=0;
}
void add(int x, int l, int a, int b, int p, int k, ll val){
if (a>k || b<p)return;
if (p<=a && b<=k){
tree[l][x]+=val;
lazy[l][x]+=val;
return;
}
daj(x,l);
int mid=(a+b)/2;
add(2*x,l,a,mid,p,k,val);
add(2*x+1,l,mid+1,b,p,k,val);
tree[l][x]=min(tree[l][2*x],tree[l][2*x+1]);
}
int query(int x, int l, int a, int b, int p, int k){
if (a>k || b<p)return 1e9;
if (p<=a && b<=k)return tree[l][x];
daj(x,l);
int mid=(a+b)/2;
return min(query(2*x,l,a,mid,p,k),query(2*x+1,l,mid+1,b,p,k));
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n,d,t;
cin >> n >> d >> t;
while(base<n)base*=2;
vector<ll> empt(4*base+9,1e9);
vector<ll> empt2(n+3,1e9);
vector<ll> empt3(4*base+9,0);
for (int x=0;x<=d+1;x++){tree[x]=empt;dp[x]=empt2;lazy[x]=empt3;}
for (int x=1;x<=n;x++){
cin >> a[x];
}
vector<pair<int,int>> stos;
stos.push_back({2e9,-1});
for (int x=1;x<=n;x++){
int rang=-1;
if (a[x]<=t)rang=x+t-a[x];
stos.push_back({rang,x});
while(stos.back().first<x)stos.pop_back();
skad[x]=stos.back().second;
}
//for (int x=1;x<=n;x++) cout << skad[x] << ' ';
//cout << '\n';
add(1,0,0,base-1,0,0,-1e9);
for (int x=1;x<=n+1;x++){
for (int y=1;y<=d+1;y++){
dp[y][x]=query(1,y-1,0,base-1,0,x-1);
add(1,y,0,base-1,x,x,dp[y][x]-1e9);
}
if (skad[x]!=-1){
for (int y=0;y<=d+1;y++)add(1,y,0,base-1,0,skad[x],1);
}
/*for (int x=0;x<=n;x++) cout << query(1,0,0,base-1,x,x) << ' ';
cout << '\n';
for (int x=0;x<=n;x++) cout << query(1,1,0,base-1,x,x) << ' ';
cout << '\n';
for (int x=0;x<=n;x++) cout << query(1,2,0,base-1,x,x) << ' ';
cout << '\n';
cout << '\n';*/
}
//cout << dp[1][2] << '\n';
//cout << dp[2][4] << '\n';
cout << dp[d+1][n+1] << '\n';
return 0;
}
