zoukankan      html  css  js  c++  java
  • HDU-2647 Reward(拓扑排序)

    Reward

    Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
    Total Submission(s): 9799    Accepted Submission(s): 3131


    Problem Description
    Dandelion's uncle is a boss of a factory. As the spring festival is coming , he wants to distribute rewards to his workers. Now he has a trouble about how to distribute the rewards.
    The workers will compare their rewards ,and some one may have demands of the distributing of rewards ,just like a's reward should more than b's.Dandelion's unclue wants to fulfill all the demands, of course ,he wants to use the least money.Every work's reward will be at least 888 , because it's a lucky number.
     
    Input
    One line with two integers n and m ,stands for the number of works and the number of demands .(n<=10000,m<=20000)
    then m lines ,each line contains two integers a and b ,stands for a's reward should be more than b's.
     
    Output
    For every case ,print the least money dandelion 's uncle needs to distribute .If it's impossible to fulfill all the works' demands ,print -1.
     
    Sample Input
    2 1
    1 2
     
    2 2
    1 2
    2 1
     
    Sample Output
    1777
    -1
     
    Author
    dandelion
    #include<iostream>
    #include<cstring>
    #include<cstdio>
    #include<vector>
    #include<queue>
    
    using namespace std;
    const int N = 10000 + 15;
    int n, m, in[N], val[N];
    vector<int> edge[N];
    
    void Solve_question(){
        int ans = 0, cnt = 0;
        queue <int> Q;
    
        for(int i = 1; i <= n; i++)
            if(!in[i]) { Q.push(i); val[i] = 888; }
        while(!Q.empty()){
            int u = Q.front(); Q.pop();
            cnt++;
            for(int i = 0; i < (int)edge[u].size(); i++){
                int v = edge[u][i];
                if(--in[v] == 0){
                    Q.push(v);
                    val[v] = val[u] + 1;
                }
            }
        }
        if(cnt < n) puts("-1");
        else{
            for(int i = 1; i <= n; i++)
                ans += val[i];
            printf("%d
    ", ans);
        }
    }
    
    void Input_data(){
        for(int i = 1; i <= n; i++) edge[i].clear(), val[i] = in[i] = 0;
        int u, v;
        for(int i = 1; i <= m; i++){
            scanf("%d %d", &u, &v);
            in[u]++;
            edge[v].push_back(u);
        }
    }
    
    int main(){
        while(scanf("%d %d", &n, &m) == 2){
            Input_data();
            Solve_question();
        }
    }

    转载于:https://www.cnblogs.com/Pretty9/p/7413231.html

  • 相关阅读:
    安卓5.1/7.1/8.1+wifi有叉问题解决
    历史市盈率查询
    IE9 Windows7 x64
    Error while loading shared libraries: libpq.so.5: cannot open shared object file: No such file or directory
    ubuntu kylin 13.10 无法安装ia32-libs解决方案
    ajax报错问题的解决
    关于 java swing 使用按钮关闭窗口
    关于在filter中获取WebApplicationContext的实践
    spring security
    毕设项目,系统搭建笔记文档
  • 原文地址:https://www.cnblogs.com/twodog/p/12139574.html
Copyright © 2011-2022 走看看