//看看会不会爆int!数组会不会少了一维！
//取物问题一定要小心先手胜利的条件
#include <bits/stdc++.h>
using namespace std;
#pragma comment(linker,"/STACK:102400000,102400000")
#define LL long long
#define ALL(a) a.begin(), a.end()
#define pb push_back
#define mk make_pair
#define fi first
#define se second
#define haha printf("haha\n")
const int inf = 1e9 + 5;
const int maxn = 40000 + 5;
int n, root[maxn], tot;
struct Tree{
    int lnub, rnub, val;
}tree[maxn * 100];
LL ans;

int update(int o, int ql, int qr, int l, int r, int cost){
    int k = ++tot;
    tree[k] = tree[o];
    if (ql <= l && qr >= r) {
        tree[k].val = max(tree[k].val, cost);
        return k;
    }
    int mid = (l + r) / 2;
    if (ql <= mid) tree[k].lnub = update(tree[o].lnub, ql, qr, l, mid, cost);
    if (qr > mid) tree[k].rnub = update(tree[o].rnub, ql, qr, mid + 1, r, cost);
    return k;
}

void push_down(int o){
    int lb = tree[o].lnub, rb = tree[o].rnub;
    tree[lb].val = max(tree[lb].val, tree[o].val);
    tree[rb].val = max(tree[rb].val, tree[o].val);
}

void query(int o, int l, int r){
    if (!tree[o].lnub && !tree[o].rnub){
        ans = ans + 1LL * (r - l + 1) * tree[o].val;
        return ;
    }
    push_down(o);
    int mid = (l + r) / 2;
    if (tree[o].lnub) query(tree[o].lnub, l, mid);
    if (tree[o].rnub) query(tree[o].rnub, mid + 1, r);
    if (!tree[o].lnub) ans = ans + 1LL * (mid - l + 1) * tree[o].val;
    if (!tree[o].rnub) ans = ans + 1LL * (r - mid) * tree[o].val;
}

int main(){
    cin >> n;
    for (int i = 1; i <= n; i++){
        int a, b, k; scanf("%d%d%d", &a, &b, &k);
        root[i] = update(root[i - 1], a, b-1, 1, inf, k);
    }
    query(root[n], 1, inf);
    cout << ans << endl;
    return 0;
}