dfs枚举搜索,遇到较小的路径就替换,搜索的状态为每头牛选与不选,在数目大于ans的时候直接return,
code:
/* ID: yueqiq LANG: C++ TASK: holstein */ #include <set> #include <map> #include <ctime> #include <queue> #include <cmath> #include <stack> #include <limits> #include <vector> #include <bitset> #include <string> #include <cstdio> #include <cstring> #include <fstream> #include <string.h> #include <iostream> #include <algorithm> #define ls rt<<1 #define rs rt<<1|1 #define Si set<int> #define LL long long #define pb push_back #define PS printf(" ") #define Vi vector<int> #define LN printf("\n") #define SD(a) scanf("%d",&a) #define PD(a) printf("%d",a) #define SET(a,b) memset(a,b,sizeof(a)) #define FF(i,a) for(int i(0);i<(a);i++) #define FD(i,a) for(int i(a);i>=(1);i--) #define FOR(i,a,b) for(int i(a);i<=(b);i++) #define FOD(i,a,b) for(int i(a);i>=(b);i--) #define readf freopen("holstein.in","r",stdin) #define writef freopen("holstein.out","w",stdout) const double pi = acos(-1.0); const int maxn = 50; const int BigP = 99999999; const int INF = 99999999; const int dx[]={0,1,0,-1}; const int dy[]={1,0,-1,0}; using namespace std; int N,M,path[maxn],ans=INF,res[maxn]={INF}; int a[maxn][maxn]; int lim[maxn],now[maxn]; bool check(int *a,int *b,int num){ FOR(i,1,num) if(a[i]<b[i]) return false; return true; } //dfs搜索第K中饲料选或是不选 void dfs(int k,int num){ // puts("----------------------------"); // FOR(i,1,N) printf("%d ",now[i]);LN; // printf("k:%d num:%d ans:%d\n",k,num,ans); // puts("----------------------------"); if(k>M+1) return ; if(num>ans) return ; if(check(now,lim,N)){ bool flag=false; if(num==ans){ FOR(i,0,ans-1) if(path[i]<res[i]){ flag=true; break; } }else{ ans=num; flag=true; } if(flag){ FOR(i,0,ans-1) res[i]=path[i]; } return; } FOR(i,1,N) now[i]+=a[k][i]; path[num]=k; dfs(k+1,num+1); FOR(i,1,N) now[i]-=a[k][i]; path[num]=0; dfs(k+1,num); } int main(){ readf; writef; SD(N); FOR(i,1,N) SD(lim[i]); SD(M); FOR(i,1,M) FOR(j,1,N){ SD(a[i][j]); } dfs(0,0); PD(ans);PS; FOR(i,0,ans-2){ printf("%d ",res[i]); } printf("%d\n",res[ans-1]); return 0; }