#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using pll = pair<ld, int>;
#define f first
#define s second
bool operator < (pll x, pll y){
if (x.f == y.f){
return x.s < y.s;
}
if (x.f > y.f) return 1;
return 0;
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, d, t; cin>>n>>d>>t;
vector<int> a(n + 1);
for (int i = 1; i <= n; i++){
cin>>a[i];
}
vector<vector<int>> h(n + 1, vector<int>(n + 1));
for (int i = 1; i <= n; i++){
int mx = 0, cnt = 0;
for (int j = i; j <= n; j++){
if (a[j] <= t){
int m = t - a[j];
mx = max(mx, j + m);
}
cnt += (j <= mx);
h[i][j] = cnt;
}
}
auto solve = [&](ld m){
pll dp[n + 1];
for (int i = 1; i <= n; i++){
dp[i] = {h[1][i], 0};
for (int j = 1; j < i; j++){
// [1, j] | [j + 1, i]
dp[i] = min(dp[i], {dp[j].f + h[j + 1][i] + m, dp[j].s + 1});
}
}
return dp[n];
};
ld l = 0, r = n;
int tt = 30;
while (tt--){
ld m = (l + r) / 2;
auto [v, k] = solve(m);
if (k > d){
l = m;
}
else {
r = m;
}
}
auto [v, k] = solve(l);
cout<<round(v - l * d)<<"\n";
}
