Submission #58676672

---

Source Code Expand

#ifndef loc
#pragma GCC optimize ("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize ("unroll-loops")
#endif
#include <bits/stdc++.h>
#define fo(i,n) for(long long i = 0; i < n; i++)
#define foa(i,k,n) for(long long i = k; i < n; i++)
#define fob(i,k,n) for(long long i = k; i >= n; i--)
#define pb push_back
#define F first
#define S second
#define sz(x) int((x).size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sortuniq(v) {sort(v.begin(), v.end()); v.erase(unique(v.begin(), v.end()), v.end());}
#define uniq(v) {v.erase(unique(v.begin(), v.end()), v.end());}
#define uid(a, b) uniform_int_distribution<int>(a, b)(rng)
using namespace std;  using ld = long double; using ll = long long; using vi = vector<int>; using vvi = vector<vi>; using vll = vector<ll>; using vvll = vector<vll>; using vb = vector<bool>; using vvb = vector<vb>; using pii = pair<int, int>; using pll = pair<ll, ll>; using vpii = vector<pii>; using vpll = vector<pll>; using arl2 = array<ll, 2>; using arl3 = array<ll, 3>; template <typename T> void ckmin(T &a, const T &b) { a = min(a, b); } template <typename T> void ckmax(T &a, const T &b) { a = max(a, b); } namespace __input {template <class T1, class T2> void re(pair<T1, T2> &p);template <class T> void re(vector<T> &a);template <class T, size_t SZ> void re(array<T, SZ> &a);template <class T> void re(T &x) { cin >> x; }void re(double &x) { string t; re(t); x = stod(t); }template <class Arg, class... Args> void re(Arg &first, Args &...rest) { re(first); re(rest...); }template <class T1, class T2> void re(pair<T1, T2> &p) { re(p.f, p.s); }template <class T> void re(vector<T> &a) { for (int i = 0; i < sz(a); i++) re(a[i]); }template <class T, size_t SZ> void re(array<T, SZ> &a) { for (int i = 0; i < SZ; i++) re(a[i]); }} using namespace __input;
namespace __output {template <typename T> struct is_outputtable { template <typename C> static constexpr decltype(declval<ostream &>() << declval<const C &>(), bool()) test(int) { return true; } template <typename C> static constexpr bool test(...) { return false; } static constexpr bool value = test<T>(int()); };template <class T, typename V = decltype(declval<const T &>().begin()), typename S = typename enable_if<!is_outputtable<T>::value, bool>::type> void pr(const T &x);template <class T, typename V = decltype(declval<ostream &>() << declval<const T &>())> void pr(const T &x) { cout << x; }template <class T1, class T2> void pr(const pair<T1, T2> &x);template <class Arg, class... Args> void pr(const Arg &first, const Args &...rest) { pr(first); pr(rest...); }template <class T, bool pretty = true> void prContain(const T &x) { if (pretty) pr("{"); bool fst = 1; for (const auto &a : x) pr(!fst ? pretty ? ", " : " " : "", a), fst = 0; if (pretty) pr("}"); }template <class T> void pc(const T &x) { prContain<T, false>(x); pr("\n"); }template <class T1, class T2> void pr(const pair<T1, T2> &x) { pr("{", x.f, ", ", x.s, "}"); }template <class T, typename V, typename S> void pr(const T &x) { prContain(x); }void ps() { pr("\n"); }template <class Arg> void ps(const Arg &first) { pr(first); ps(); }template <class Arg, class... Args> void ps(const Arg &first, const Args &...rest) { pr(first, " "); ps(rest...); }} using namespace __output;
#define __pn(x) pr(#x, " = ")
#define pd(...) __pn((__VA_ARGS__)), ps(__VA_ARGS__), cout << flush
#define noo {ps("NO");return;}
#define yess {ps("YES");return;}
#define Multitests 0 //#define int long long

void solve(){
	ll n; cin >> n;
	pll prev = {0, 0};
	double ans = 0;
	fo(i, n+1){
		ll x, y; 
		if(i<n) cin >> x >> y;
		else x=y=0;
		double  distx = abs(x - prev.F);
		double disty = abs(y - prev.S);
		double dist = distx*distx + disty*disty;
		dist = sqrt(dist);
		ans += dist;
		prev={x,y};
	}
	ps(ans);
}

int32_t main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout << setprecision(15);
	if(Multitests){
		int t; cin >> t;  fo(i, t) solve();
	}else solve();
    return 0;
}

Submission Info

Judge Result