第一次把题意理解错了,第二次因为一个 ] ,wrong了四次,还好在极值样例的检测下,找出来了。以后打代码一定要注意了。
我是这样定义状态的,f[i][j]表示在第i天时,在城市j所花费的最小费用,很简单的dp题:
代码如下:
#include<stdio.h> #include<string.h> #define INF 2000000000 long long b[15][15][35]; long long f[1010][15]; int n, k, num; void output() { if(f[k+1][n] < INF)printf("The best flight costs %lld.\n",f[k+1][n]); else printf("No flight possible.\n"); printf("\n"); } void solve() { for(int i = 2; i <= n; i ++) f[1][i] = INF; f[1][1] = 0; for(int i = 2; i <= k+1; i ++) for(int j = 1; j <= n; j ++) { f[i][j] = INF; for(int g = 1; g <= n; g ++) if(g != j && f[i-1][g] != INF) { if((i-1)%b[g][j][0]&&f[i-1][g]+b[g][j][(i-1)%b[g][j][0]] < f[i][j]) f[i][j] = f[i-1][g] + b[g][j][(i-1)%b[g][j][0]]; if(!((i-1)%b[g][j][0]) && f[i-1][g] + b[g][j][b[g][j][0]] < f[i][j]) f[i][j] = f[i-1][g] + b[g][j][b[g][j][0]]; } } output(); } void input() { while(scanf("%d%d",&n, &k) == 2) { if(n==0&&k==0) break; for(int i = 1; i <= n; i ++) for(int j = 1; j <= n; j ++) if(i != j) { scanf("%d",&b[i][j][0]); for(int g = 1; g <= b[i][j][0]; g ++) { scanf("%d",&b[i][j][g]); if(b[i][j][g] == 0) b[i][j][g] = INF; } } printf("Scenario #%d\n",++num); solve(); } } int main() { num = 0; input(); return 0; }