zoukankan      html  css  js  c++  java
  • Codeforces Round #283 (Div. 2) C. Removing Columns 暴力

    C. Removing Columns
    time limit per test
    2 seconds
    memory limit per test
    256 megabytes
    input
    standard input
    output
    standard output

    You are given an n × m rectangular table consisting of lower case English letters. In one operation you can completely remove one column from the table. The remaining parts are combined forming a new table. For example, after removing the second column from the table


    abcd
    edfg
    hijk

    we obtain the table:


    acd
    efg
    hjk

    A table is called good if its rows are ordered from top to bottom lexicographically, i.e. each row is lexicographically no larger than the following one. Determine the minimum number of operations of removing a column needed to make a given table good.

    Input

    The first line contains two integers  — n and m (1 ≤ n, m ≤ 100).

    Next n lines contain m small English letters each — the characters of the table.

    Output

    Print a single number — the minimum number of columns that you need to remove in order to make the table good.

    Sample test(s)
    Input
    1 10
    codeforces
    Output
    0
    Input
    4 4
    case
    care
    test
    code
    Output
    2
    Input
    5 4
    code
    forc
    esco
    defo
    rces
    Output
    4
    Note

    In the first sample the table is already good.

    In the second sample you may remove the first and third column.

    In the third sample you have to remove all the columns (note that the table where all rows are empty is considered good by definition).

    Let strings s and t have equal length. Then, s is lexicographically larger than t if they are not equal and the character following the largest common prefix of s and t (the prefix may be empty) in s is alphabetically larger than the corresponding character of t.

    看题意 我看了好久……

    #include <cstdio>
    #include <cmath>
    #include <cstring>
    #include <ctime>
    #include <iostream>
    #include <algorithm>
    #include <set>
    #include <vector>
    #include <sstream>
    #include <queue>
    #include <typeinfo>
    #include <fstream>
    typedef long long ll;
    using namespace std;
    //freopen("D.in","r",stdin);
    //freopen("D.out","w",stdout);
    #define sspeed ios_base::sync_with_stdio(0);cin.tie(0)
    #define maxn 100001
    const int inf=0x7fffffff;   //无限大 
    int n,m,res;
    char c[2000][2000];
    string s[2000];
    int main()
    {
        cin >> n >> m;
        for( int i=0; i<n; i++)
            for( int h=0; h<m; h++)
                cin >> c[i][h];
        bool b=0;
        for( int i=0; i<m; i++ )
        {
            for( int h=1; h<n; h++ )
            {
                if( s[h-1]+c[h-1][i] > s[h]+c[h][i] )
                {
                    b=1;
                    break;
                }
            }
            if(!b)
            {
                for(int h=0;h<n;h++)
                    s[h]+=c[h][i];
            }    b=0;
        }
        cout << m-s[0].length();
        return 0;
    }
  • 相关阅读:
    索引与完整性约束(note6)
    数据库查询语句(note4)
    select 查询(note3)
    数据库创建(note2)
    mysql(note1)
    day 05
    day 04 字符串
    博文索引
    ubuntu+xen的编译
    hexo+github搭建个人网站
  • 原文地址:https://www.cnblogs.com/qscqesze/p/4172255.html
Copyright © 2011-2022 走看看