E:By Elevator or Stairs? CF595 DP最短路
生活随笔
收集整理的這篇文章主要介紹了
E:By Elevator or Stairs? CF595 DP最短路
小編覺(jué)得挺不錯(cuò)的,現(xiàn)在分享給大家,幫大家做個(gè)參考.
題目鏈接
比賽的時(shí)候一看,這不是最短路嗎,然后敲了一個(gè)最短路。
然后比賽完發(fā)現(xiàn)大家基本都寫(xiě)的dp,我真是個(gè)憨憨,dp3行
最短路就建個(gè)簡(jiǎn)單的圖,dp就是從上一維轉(zhuǎn)化過(guò)來(lái)就是了
優(yōu)秀的dp:
//#pragma comment (linker, "/STACK:102400000,102400000")
#include<bits/stdc++.h>
#include<stdio.h>
#include<string.h>
#include<string>
#include<iostream>
#include<algorithm>
#include<math.h>
#include<set>
#include<stack>
#include<vector>
#include<map>
#include<queue>
#include<list>
#include<time.h>
#define myself i,l,r
#define lson i<<1
#define rson i<<1|1
#define Lson i<<1,l,mid
#define Rson i<<1|1,mid+1,r
#define half (l+r)/2
#define lowbit(x) x&(-x)
#define min4(a, b, c, d) min(min(a,b),min(c,d))
#define min3(x, y, z) min(min(x,y),z)
#define max3(x, y, z) max(max(x,y),z)
#define max4(a, b, c, d) max(max(a,b),max(c,d))
//freopen("E://1.in","r",stdin);
//freopen("E://1.out","w",stdout);
typedef unsigned long long ull;
typedef long long ll;
#define pii make_pair
#define pr pair<int,int>
const int inff = 0x3f3f3f3f;
const int dir[4][2] = {0, 1, 0, -1, 1, 0, -1, 0};
const int mdir[8][2] = {0, 1, 0, -1, 1, 0, -1, 0, 1, 1, -1, 1, 1, -1, -1, -1};
const double eps = 1e-10;
const double PI = acos(-1.0);
const double E = 2.718281828459;
using namespace std;
const long long inFF = 9223372036854775807;
const int mod=1e9+7;
const int maxn=2e5+5;
int a[maxn],b[maxn];
int dp[maxn][2];
int main()
{ios::sync_with_stdio(false);int n,c;cin>>n>>c;for(int i=2;i<=n;i++) cin>>a[i],dp[i][0]=inff;for(int i=2;i<=n;i++) cin>>b[i],dp[i][1]=inff;dp[1][0]=0,dp[1][1]=c;for(int i=2;i<=n;i++){dp[i][0]=min(dp[i-1][0]+a[i],dp[i-1][1]+b[i]);dp[i][1]=min(dp[i-1][0]+a[i]+c,dp[i-1][1]+b[i]);dp[i][0]=min(dp[i][0],dp[i][1]);}for(int i=1;i<=n;i++) cout<<min(dp[i][0],dp[i][1])<<" ";
}
SB最短路:
//#pragma comment (linker, "/STACK:102400000,102400000")
#include<bits/stdc++.h>
#include<stdio.h>
#include<string.h>
#include<string>
#include<iostream>
#include<algorithm>
#include<math.h>
#include<set>
#include<stack>
#include<vector>
#include<map>
#include<queue>
#include<list>
#include<time.h>
#define myself i,l,r
#define lson i<<1
#define rson i<<1|1
#define Lson i<<1,l,mid
#define Rson i<<1|1,mid+1,r
#define half (l+r)/2
#define lowbit(x) x&(-x)
#define min4(a, b, c, d) min(min(a,b),min(c,d))
#define min3(x, y, z) min(min(x,y),z)
#define max3(x, y, z) max(max(x,y),z)
#define max4(a, b, c, d) max(max(a,b),max(c,d))
#define pii make_pair
#define pr pair<ll,int>
//freopen("E://1.in","r",stdin);
//freopen("E://1.out","w",stdout);
typedef unsigned long long ull;
typedef long long ll;
const int inff = 0x3f3f3f3f;
const long long inFF = 9223372036854775807;
const int dir[4][2] = {0, 1, 0, -1, 1, 0, -1, 0};
const int mdir[8][2] = {0, 1, 0, -1, 1, 0, -1, 0, 1, 1, -1, 1, 1, -1, -1, -1};
const double eps = 1e-10;
const double PI = acos(-1.0);
const double E = 2.718281828459;
using namespace std;
const int mod=1e9+7;
const int maxn=1e6+5;
int head[maxn],sign;
struct node
{int to,p,val;
}edge[maxn<<1];
int n,m;
ll d[maxn];
void init()
{for(int i=0;i<=3*n;i++) head[i]=-1;sign=0;
}
void add(int u,int v,int val)
{edge[sign]=node{v,head[u],val};head[u]=sign++;
}
void dij()
{for(int i=1;i<=3*n;i++) d[i]=inFF;d[0]=0;priority_queue<pr,vector<pr>,greater<pr> >q;q.push(pii(0,0));while(!q.empty()){pr now=q.top();q.pop();if(d[now.second]>now.first) continue;for(int i=head[now.second];~i;i=edge[i].p){int v=edge[i].to;if(d[v]>edge[i].val+d[now.second]){d[v]=edge[i].val+d[now.second];q.push(pii(d[v],v));}}}
}
int main()
{cin>>n>>m;init();int x;for(int i=1;i<n;i++)scanf("%d",&x),add(i,i+1,x);for(int i=1;i<n;i++)scanf("%d",&x),add(i+n,i+1+n,x);for(int i=1;i<=n;i++) add(i,i+2*n,0),add(i+n,i+2*n,0),add(i,i+n,m),add(i+n,i,0);add(0,1,0),add(0,1+n,m);dij();for(int i=2*n+1;i<=3*n;i++) printf("%lld%c",d[i],(i==n)?'\n':' ');
}
?
總結(jié)
以上是生活随笔為你收集整理的E:By Elevator or Stairs? CF595 DP最短路的全部?jī)?nèi)容,希望文章能夠幫你解決所遇到的問(wèn)題。
- 上一篇: Codeforces Round #35
- 下一篇: Too Many Segments CF