#include<cstdio>

#include<algorithm>

#include<queue>

using namespace std;

const int maxn=;

struct cycmax{

     int id,ed;

     bool operator < (const cycmax &a)const{

         return ed<a.ed;

     }

};

priority_queue<cycmax>cmax;

struct cycmin{

    int id,ed;

    bool operator < (const cycmin &a)const{

        return ed>a.ed;

    }

};

priority_queue<cycmin>cmin;

struct cyc{

    int l,r,num;

}a[maxn];

bool cmp(cyc a,cyc b){return a.l<b.l;}

int k,n,c,ans=,number=;

bool vis[maxn];

int main(){

    scanf("%d%d%d",&n,&k,&c);

    for(int i=;i<=n;i++){

        scanf("%d%d%d",&a[i].l,&a[i].r,&a[i].num);

    }

    sort(a+,a+n+,cmp);

    for(int i=;i<=n;i++){

        cmax.push((cycmax){i,a[i].r});

        cmin.push((cycmin){i,a[i].r});

        number+=a[i].num;

        if(a[i].l!=a[i+].l){

            while(!cmin.empty()&&cmin.top().ed<=a[i].l){

                cycmin x=cmin.top();

                if(!vis[x.id]){

                    ans+=a[x.id].num;

                    number-=a[x.id].num;

                    vis[x.id]=;

                }

                cmin.pop();

            }

            while(number>c){

                cycmax x=cmax.top();

                if(!vis[x.id]){

                    if(number-a[x.id].num>=c){

                        number-=a[x.id].num;

                        vis[x.id]=;

                        cmax.pop();

                    }

                    else{

                        a[x.id].num-=number-c;//zhu yi shun xu le!!!

                        number=c;

                    }

                }else cmax.pop();

            }

        }

    }

    while(!cmax.empty()){

        cycmax x=cmax.top();cmax.pop();

        if(!vis[x.id])ans+=a[x.id].num;

    }

    printf("%d",ans);

    return ;

}