Submission #30680

#	Time	Username	Problem	Language	Result	Execution time	Memory
30680		zoomswk	Bosses (BOI16_bosses)	C++14	100 / 100	1036 ms	2244 KiB

bosses

#include <stdio.h>
#include <vector>
#include <queue>
using namespace std;

vector<int> way[5005];
int par[5005], deg[5005];
int val[5005];

int main(){
    int n;
    scanf("%d", &n);
    for(int i=1; i<=n; i++){
        int k;
        scanf("%d", &k);
        while(k--){
            int x;
            scanf("%d", &x);
            way[x].push_back(i);
        }
    }
    int res = 1e9;
    for(int root=1; root<=n; root++){
        queue<int> q;
        q.push(root);
        for(int i=1; i<=n; i++) par[i] = 0, deg[i] = 0, val[i] = 1;
        par[root] = root;
        while(!q.empty()){
            int pos = q.front();
            q.pop();
            for(int v : way[pos]) if(!par[v]){
                q.push(v);
                par[v] = pos;
                deg[pos]++;
            }
        }
        int valid = 1;
        for(int i=1; i<=n; i++){
            if(!par[i]){ valid = 0; break; }
        }
        if(!valid) continue;
        for(int i=1; i<=n; i++) if(deg[i] == 0) q.push(i);
        int cur = 0;
        while(!q.empty()){
            int pos = q.front();
            q.pop();
            cur += val[pos];
            val[par[pos]] += val[pos];
            deg[par[pos]]--;
            if(deg[par[pos]] == 0) q.push(par[pos]);
        }
        if(cur < res) res = cur;
    }
    printf("%d", res);
    return 0;
}

Compilation message (stderr)

bosses.cpp: In function 'int main()':
bosses.cpp:12:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
                    ^
bosses.cpp:15:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &k);
                        ^
bosses.cpp:18:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &x);
                            ^

• Subtask 1: 22 / 22
• Subtask 2: 45 / 45
• Subtask 3: 33 / 33