Поток Леонида

ll t;

cin >> t;

while(t--){
    ll n;

    cin >> n;

    vector<ll> a(n);

    for(ll i = 0; i<n; i++){
        cin >> a[i];
    }

    ll ans = 0;
    ll p = a[0];
    for(ll j = 0; j < n - 1; j++){
        if(a[j] < a[j + 1]){
            ans += a[j + 1] - a[j];
        }else{
            ans += a[j] - a[j + 1];
            p -= a[j] - a[j + 1];
        }
    }
    ans += abs(p);
    cout << ans << "\n";
}

struct Point {
    ll x, y;
};

bool comp(Point &A, Point &B){
//    if ((A.x * A.x + A.y * A.y) <
//            (B.x * B.x + B.y * B.y)){
//        return 1;
//    } else {
//        return 0;
//    }
    return ((A.x * A.x + A.y * A.y) <
            (B.x * B.x + B.y * B.y));
}

int main(){
		ll n;
    cin >> n;
    vector<Point> a(n);
    for(ll i = 0; i<n; i++){
        ll x, y;
        cin >> x >> y;
        a[i].x = x;
        a[i].y = y;
    }

    sort(a.begin(), a.end(), comp);

    for(ll i = 0; i<n; i++){
        cout << a[i].x << ' ' << a[i].y << "\n";
    }
}

ll x, n;
cin >> x >> n;

vector<ll> a(n);
for(ll i = 0; i<n; i++){
    cin >> a[i];
}

ll l = 0, r = n;

while(r - l > 1){
    ll mid = (l + r) / 2;

    if(x < a[mid]){
        r = mid;
    } else {
        l = mid;
    }
}

auto it = lower_bound(a.begin(), a.end(), x);
cout << *it << "\n";

//или
ll it = lower_bound(a.begin(), a.end(), x) - a.begin();
cout << it << ' ' << a[it] << "\n";

//upper_bound() - аналогично, но возвращает строго больший элемент