刷个简单的ＤＰ缓缓心情
１Ａ
1 #include <iostream> 2 #include<cstdio> 3 #include<cstring> 4 #include<algorithm> 5 #include<stdlib.h> 6 #include<vector> 7 using namespace std; 8 #define N 10010 9 vector<int>q[N]; 10 #define LL __int64 11 #define INF 1e10 12 LL dp[N][4]; 13 int o[N]; 14 struct node 15 { 16 int x,y,d; 17 char s[10]; 18 }p[N]; 19 int main() 20 { 21 int i,j,n,m; 22 scanf("%d%d",&n,&m); 23 for(i = 1; i <= m ; i++) 24 { 25 scanf("%d%d%d%s",&p[i].x,&p[i].y,&p[i].d,p[i].s); 26 q[p[i].y].push_back(i); 27 } 28 dp[i][1] = 0; 29 dp[i][2] = INF; 30 dp[i][3] = INF; 31 for(i = 2; i <= n ; i++) 32 { 33 dp[i][1] = dp[i][2] = dp[i][3] = INF; 34 for(j = 0 ; j < (int)q[i].size() ; j++) 35 { 36 int v = q[i][j],k,x = p[v].x,w = p[v].d; 37 if(strcmp(p[v].s,"Licensed")==0) 38 k = 1; 39 else if(strcmp(p[v].s,"Cracked")==0) 40 k = 2; 41 else k = 3; 42 if(k==1) 43 { 44 dp[i][1] = min(dp[i][1],min(dp[x][1]+w,dp[x][2]+w)); 45 } 46 else if(k==2) 47 { 48 dp[i][2] = min(dp[i][2],min(dp[x][2]+w,dp[x][1]+w)); 49 dp[i][3] = min(dp[i][3],dp[x][3]+w); 50 } 51 else 52 { 53 dp[i][3] = min(dp[i][3],dp[x][3]+w); 54 dp[i][3] = min(dp[i][3],dp[x][2]+w); 55 dp[i][3] = min(dp[i][3],dp[x][1]+w); 56 } 57 } 58 } 59 LL ans = INF; 60 for(i = 1; i <= 3 ; i++) 61 ans = min(ans,dp[n][i]); 62 if(ans==INF) 63 puts("Offline"); 64 else 65 { 66 puts("Online"); 67 printf("%I64d ",ans); 68 } 69 return 0; 70 }