zoukankan      html  css  js  c++  java
  • POJ_2533 Frogger 最小瓶颈路

    题目链接:http://poj.org/problem?id=2533

    该题其实等价于求两点之间的最小瓶颈路-min(d[i][j], max(d[i][k], d[k][j])),即最短路中的最大值

    用Floyd算法可以在O(n3)内求出,鉴于此题n=200,因此直接上Floyd

     1 #include <cstdio>
     2 #include <cstdlib>
     3 #include <cmath>
     4 #include <cstring>
     5 #include <algorithm>
     6 #include <string>
     7 using namespace std;
     8 #define inf 0x3f3f3f3f
     9 #define maxm 30005
    10 #define maxn 205
    11 double d[maxn][maxn];
    12 int n, m;
    13 int x[maxn], y[maxn];
    14 
    15 void floyd(){
    16     for(int k = 0; k < n; k++){
    17         for(int i = 0; i < n; i++)
    18             for(int j = 0; j < n; j++)
    19                 d[i][j] = min(d[i][j], max(d[i][k], d[k][j]));
    20     }
    21 }
    22 
    23 int main(){
    24     int cnt = 1;
    25     while(scanf("%d", &n) && n){
    26         for(int i = 0; i < n; i++){
    27             for(int j = 0; j < n; j++){
    28                 if(i == j) d[i][j] = 0;
    29                 d[i][j] = inf;
    30             }
    31         }
    32         for(int i = 0; i < n; i++){
    33             scanf("%d %d", &x[i], &y[i]);
    34         }
    35         for(int i = 0; i < n; i++){
    36             for(int j = 0; j < n; j++){
    37                 d[i][j] = sqrt(pow(x[i] - x[j], 2) + pow(y[i] - y[j], 2));
    38             }
    39         }
    40         floyd();
    41         printf("Scenario #%d
    ", cnt++);
    42         printf("Frog Distance = %.3f
    
    ", d[0][1]);
    43     }
    44 }

    题目:

    Longest Ordered Subsequence
    Time Limit: 2000MS   Memory Limit: 65536K
    Total Submissions: 51551   Accepted: 22931

    Description

    A numeric sequence of ai is ordered if a1 < a2 < ... < aN. Let the subsequence of the given numeric sequence (a1a2, ..., aN) be any sequence (ai1ai2, ..., aiK), where 1 <= i1 < i2 < ... < iK <= N. For example, sequence (1, 7, 3, 5, 9, 4, 8) has ordered subsequences, e. g., (1, 7), (3, 4, 8) and many others. All longest ordered subsequences are of length 4, e. g., (1, 3, 5, 8).

    Your program, when given the numeric sequence, must find the length of its longest ordered subsequence.

    Input

    The first line of input file contains the length of sequence N. The second line contains the elements of sequence - N integers in the range from 0 to 10000 each, separated by spaces. 1 <= N <= 1000

    Output

    Output file must contain a single integer - the length of the longest ordered subsequence of the given sequence.

    Sample Input

    7
    1 7 3 5 9 4 8

    Sample Output

    4
  • 相关阅读:
    MongoDB+模板引擎 项目实例-学生档案管理
    MongoDB 增删改查命令速查
    MongoDB 数据库概述及环境搭建
    Flutter 升级
    TypeScript 快速上手及学习笔记
    Android ContentProvider 启动分析
    HTTP 报文格式简介
    深入浅出 HTTPS (详解版)
    从你输入网址,到看到网页——详解中间发生的过程
    TCP 三次握手和四次挥手图解(有限状态机)
  • 原文地址:https://www.cnblogs.com/bolderic/p/6815765.html
Copyright © 2011-2022 走看看