Submission #203873

#	Time	Username	Problem	Language	Result	Execution time	Memory
203873		cheetose	Olympic Bus (JOI20_ho_t4)	C++11	11 / 100	1095 ms	2296 KiB

ho_t4

#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define X first
#define Y second
#define y0 y12
#define y1 y22
#define INF 987654321987654321
#define PI 3.141592653589793238462643383279502884
#define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
#define fdn(i,a,b,c) for(int (i)=(a);(i)>=(b);(i)-=(c))
#define MEM0(a) memset((a),0,sizeof(a));
#define MEM_1(a) memset((a),-1,sizeof(a));
#define ALL(a) a.begin(),a.end()
#define SYNC ios_base::sync_with_stdio(false);cin.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
typedef pair<ld, ld> Pd;
typedef vector<int> Vi;
typedef vector<ll> Vll;
typedef vector<double> Vd;
typedef vector<Pi> VPi;
typedef vector<Pll> VPll;
typedef vector<Pd> VPd;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef tuple<ll, ll, ll> LLL;
typedef vector<iii> Viii;
typedef vector<LLL> VLLL;
typedef complex<double> base;
const int MOD = 998244353;
ll POW(ll a, ll b, ll MMM = MOD) { ll ret = 1; for (; b; b >>= 1, a = (a*a) % MMM)if (b & 1)ret = (ret*a) % MMM; return ret; }
ll gcd(ll a, ll b) { return b ? gcd(b, a%b) : a; }
ll lcm(ll a, ll b) { if (a == 0 || b == 0)return a + b; return a*(b / gcd(a, b)); }
int dx[] = { 0,1,0,-1,1,1,-1,-1 }, dy[] = { 1,0,-1,0,1,-1,1,-1 };

ll dist[201][201],tmp[201][201];
int x[50000],y[50000];
ll c[50000],d[50000];
int n,m;
ll floyd(int kk,ll d[201][201])
{
	fup(i,1,n,1)fup(j,1,n,1)d[i][j]=(i==j?0:INF);
	fup(i,0,m-1,1)
	{
		if(i==kk)d[y[i]][x[i]]=min(d[y[i]][x[i]],c[i]);
		else d[x[i]][y[i]]=min(d[x[i]][y[i]],c[i]);
	}
	fup(k,1,n,1)fup(i,1,n,1)fup(j,1,n,1)
	{
		d[i][j]=min(d[i][j],d[i][k]+d[k][j]);
	}
}
bool ok(int S,int E,int u,int v,ll c){return dist[S][u]<INF && dist[S][u]+dist[u][v]+dist[v][E]==dist[S][E] && dist[S][u]+c==dist[S][v];}
int main() {
	scanf("%d%d",&n,&m);
	fup(i,0,m-1,1)scanf("%d%d%lld%lld",x+i,y+i,c+i,d+i);
	floyd(-1,dist);
	ll ans=dist[1][n]+dist[n][1];
	fup(i,0,m-1,1)
	{
		if(ok(1,n,x[i],y[i],c[i]) || ok(n,1,x[i],y[i],c[i]))
		{
			floyd(i,tmp);
			ans=min(ans,d[i]+tmp[1][n]+tmp[n][1]);
		}
		else
		{
			ll tmp=d[i]+min({dist[1][y[i]]+c[i]+dist[x[i]][n]+dist[n][1],dist[1][n]+dist[n][y[i]]+c[i]+dist[x[i]][1],dist[1][y[i]]+c[i]+dist[x[i]][n]+dist[n][y[i]]+c[i]+dist[x[i]][1]});
			ans=min(ans,tmp);
		}
	}
	if(ans>=INF)ans=-1;
	printf("%lld",ans);
}

Compilation message (stderr)

ho_t4.cpp: In function 'll floyd(int, ll (*)[201])':
ho_t4.cpp:59:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
ho_t4.cpp: In function 'int main()':
ho_t4.cpp:62:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ~~~~~^~~~~~~~~~~~~~
ho_t4.cpp:63:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  fup(i,0,m-1,1)scanf("%d%d%lld%lld",x+i,y+i,c+i,d+i);
                ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 11 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 63