#include<bits/stdc++.h>
#define endl '\n'
#define int long long
using namespace std;
const int debug = 0;
const int N = 1e5+20;
map <int, vector <int>> tempos;
int32_t main(){
int n, k, x;
cin >> n >> k >> x;
for(int i = 0;i < n;i++){
int l, t, r;
cin >> l >> t >> r;
tempos[l].push_back(0);
tempos[r+1].push_back(1);
tempos[l+t].push_back(2);
tempos[r+1].push_back(3);
}
int r = 0, l = -x+1;
int qtdl = 0, qtdr = 0, vall = 0, valr = 0;
int res = 0, soma = 0;
while(tempos.upper_bound(r) != tempos.end()){
//cout << l << ' ' << r << endl;
auto it = tempos.upper_bound(l);
int l1 = it->first;
it = tempos.upper_bound(r);
int r1 = it->first;
//cout << l1 << ' ' << r1 << endl;
if(l1-l < r1-r){
// vou do [l, r] ate [l1-1, l1-1+x-1]
// l1-l
soma -= (qtdl >= k)*vall*(l1-l-1);
// l1-1+x-r
soma += (qtdr >= k)*valr*(l1+x-r-2);
res = max(res, soma);
l = l1-1;
r = l1-1+x-1;
soma -= (qtdl >= k)*vall;
l++;
r++;
for(auto typ : tempos[l]){
if(typ == 0) qtdl++;
if(typ == 1) qtdl--;
if(typ == 2) vall++;
if(typ == 3) vall--;
}
soma += (qtdr >= k)*valr;
res = max(res, soma);
}
else if(l1-l > r1-r){
// vou do [l, r] ate [r1-x, r1-1]
//r1-x-l+1
soma -= (qtdl >= k)*vall*(r1-x-l);
soma += (qtdr >= k)*valr*(r1-r-1);
res = max(res, soma);
l = r1-x;
r = r1-1;
soma -= (qtdl >= k)*vall;
l++;
r++;
for(auto typ : tempos[r]){
if(typ == 0) qtdr++;
if(typ == 1) qtdr--;
if(typ == 2) valr++;
if(typ == 3) valr--;
}
soma += (qtdr >= k)*valr;
res = max(res, soma);
}
else{
soma -= (qtdl >= k)*vall*(r1-x-l);
soma += (qtdr >= k)*valr*(r1-r-1);
res = max(res, soma);
l = l1-1;
r = l1-1+x-1;
soma -= (qtdl >= k)*vall;
l++;
r++;
for(auto typ : tempos[l]){
if(typ == 0) qtdl++;
if(typ == 1) qtdl--;
if(typ == 2) vall++;
if(typ == 3) vall--;
}
for(auto typ : tempos[r]){
if(typ == 0) qtdr++;
if(typ == 1) qtdr--;
if(typ == 2) valr++;
if(typ == 3) valr--;
}
soma += (qtdr >= k)*valr;
res = max(res, soma);
}
}
cout << res << endl;
return 0;
}
