Submission #628501

#	Time	Username	Problem	Language	Result	Execution time	Memory
628501		duytuandao21	Toll (BOI17_toll)	C++17	25 / 100	3070 ms	56436 KiB

toll

#include<iostream>
#include<cmath>
#include<algorithm>
#include<stack>
#include<queue>
#include<deque>
using namespace std;
#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)
#define fi first
#define se second
#define ll long long
#define mp make_pair
#define pb push_back
#define ii pair<ll, int>
#define task "test"

const int inf = 1e9 + 7;
const ll infll = (ll)1e18 + 7;
const int MOD = 1e9 + 7;
const int N = 2e6 + 3;

template <typename T1, typename T2> bool minimize(T1 &a, T2 b){if (a > b) {a = b; return true;} return false;}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b){if (a < b) {a = b; return true;} return false;}

int k,n,m,q;
int par[N], s[N];
int u[N], v[N];
vector<ii> adj[N];
struct ha {
	int x,y,z;
};
ha a[N];
bool sor(const ha X, const ha Y) {
	return X.x < Y.x;
}

void solve(int x,int y) {
    vector<ll> d(n+1, inf);
    d[x] = 0;
    priority_queue< ii, vector<ii>, greater<ii> > p;
    p.push(mp(0,x));
    while(!p.empty()) {
        int u = p.top().se;
        int val = p.top().fi; p.pop();
        if(val != d[u]) continue;
        for(ii X : adj[u]) {
            int v = X.se;
            int he = X.fi;
            if(d[v] > val + he) {
                d[v] = val + he;
                p.push(mp(d[v], v));
            }
        }
    }
    if(d[y] == inf) cout<<-1<<'\n'; else cout<<d[y]<<'\n';
}
int getroot(int x) {
	if(par[x] == x) return x;
	return par[x] = getroot(par[x]);
}
void join(int x,int y) {
	x = getroot(x);
	y = getroot(y);
	if(x == y) return;
	par[x] = y;
	s[y] = s[x] + adj[x][0].fi;
}
void sub1() {
	for(int i=1;i<=n;i++) par[i] = i;
	for(int i=1;i<=m;i++) {
		//cout<<a[i].x<<" "<<a[i].y<<'\n';
		join(a[i].x, a[i].y);
	}
	for(int i=1;i<=q;i++) {
		if(getroot(u[i]) != getroot(v[i])) cout<<-1<<'\n'; else 
			cout<<s[v[i]] - s[u[i]]<<'\n';
	}
	//cout<<s[4];
}
void sub2() {
	vector<ll> d(n+1, inf);
    d[0] = 0;
    priority_queue< ii, vector<ii>, greater<ii> > p;
    p.push(mp(0,0));
    while(!p.empty()) {
        int u = p.top().se;
        int val = p.top().fi; p.pop();
        if(val != d[u]) continue;
        for(ii X : adj[u]) {
            int v = X.se;
            int he = X.fi;
            if(d[v] > val + he) {
                d[v] = val + he;
                p.push(mp(d[v], v));
            }
        }
    }
	for(int i=1;i<=q;i++) {
		if(d[v[i]] == inf) cout<<-1<<'\n'; else cout<<d[v[i]]<<'\n';
	}
}
void bruteforce() {
	for(int i=1;i<=q;i++) {
		solve(u[i], v[i]);
	}
}
int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);	
	// freopen(task".inp" , "r" , stdin);
	// freopen(task".out" , "w" , stdout);
	cin>>k>>n>>m>>q;
	for(int i=1;i<=m;i++) {
        int u,v,w; cin>>u>>v>>w;
		a[i] = {u,v,w};
		adj[u].pb(mp(w,v));
		//join(u,v);
	}
	sort(a+1,a+1+m,sor);
	int count_sub2 = 0;
	for(int i=1;i<=q;i++) {
		cin>>u[i]>>v[i];
		if(u[i] == 0) count_sub2++;
	}
	if(k == 1) sub1(); else 
	if(count_sub2 == q) sub2(); else 
	bruteforce();

    return 0;
}
/* 5 14 5 5
0 5 9
5 12 10
0 7 7
7 12 8
4 7 10
0 12
0 5
0 7
7 12
0 13 */

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 8 / 8
• Subtask 4: 0 / 31
• Subtask 5: 0 / 44