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C++:如何在字符串中提取有效字符串?

extraction parsing string c++

xian · 技术社区 · 15 年前

问题是:

细节:

游戏名称最多可包含31个字符
有三种游戏模式类别:主要、次要和杂项
- 只能选择1个主要游戏模式
- 某些主要游戏模式与某些次要游戏模式不兼容
- 某些辅助游戏模式与其他辅助游戏模式不兼容
- 其他游戏模式可与所有其他游戏模式组合

以下是各种游戏模式的列表,图表显示了每种模式与哪些次要模式兼容(X表示不兼容):

// Only 1 primary allowed
static char *Primary[] = {
          // Compatible with > | dm | rv | mm | du | sh | aa | ai | as | id | em | np | sc | om | nt | nm | nb | ro | mo | sp | 
    "ap", // All Pick          |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "ar", // All Random        |    | X  |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "tr", // Team Random       | X  | X  |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "mr", // Mode Random       | X  | X  |    |    | X  | X  | X  | X  |    |    |    |    |    |    |    |    | X  | X  |    |
    "lm", // League Mode       | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  |    |
    "rd", // Random Draft      | X  | X  | X  |    | X  | X  | X  | X  |    |    |    |    |    |    |    |    | X  | X  |    |
    "vr", // Vote Random       | X  | X  | X  |    | X  | X  | X  | X  |    |    |    |    |    |    |    |    | X  | X  |    |
    "el", // Extended League   | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  |    |
    "sd", // Single Draft      | X  | X  | X  |    | X  | X  | X  | X  |    |    |    |    |    |    |    |    | X  | X  |    |
    "cm", // Captains Mode     | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  | X  |
    "cd"  // Captains Draft    | X  | X  | X  |    | X  | X  | X  | X  |    |    |    |    |    |    |    |    | X  | X  |    |
};

static char *Secondary[] = {
          // Compatible with > | dm | rv | mm | du | sh | aa | ai | as | id | em | np | sc | om | nt | nm | nb | ro | mo | sp | 
    "dm", // Death Match       |    | X  | X  |    | X  | X  | X  | X  |    |    |    |    |    |    |    |    | X  | X  |    |
    "rv", // Reverse Mode      | X  |    |    |    | X  |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "mm", // Mirror Match      | X  |    |    |    | X  |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "du", // Duplicate Mode    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "sh", // Same Hero         | X  | X  | X  |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "aa", // All Agility       | X  |    |    |    |    |    | X  | X  |    |    |    |    |    |    |    |    |    |    |    |
    "ai", // All Intelligence  | X  |    |    |    |    | X  |    | X  |    |    |    |    |    |    |    |    |    |    |    |
    "as", // All Strength      | X  |    |    |    |    | X  | X  |    |    |    |    |    |    |    |    |    |    |    |    |
    "id", // Item Drop         |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "em", // Easy Mode         |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "np", // No Powerups       |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "sc", // Super Creeps      |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    | 
    "om", // Only Mid          |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "nt", // No Top            |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "nm", // No Middle         |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
    "nb", // No Bottom         |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    | 
    "ro", // Range Only        | X  |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    | X  |    | 
    "mo", // Melee Only        | X  |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    | X  |    |    | 
    "sp"  // Shuffle Players   |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |    |
};

// These options are always available
static char *Misc[] = {
    "ns", // No Swap
    "nr", // No Repick
    "ts", // Terrain Snow
    "pm", // Pooling Mode
    "oi", // Observer Info
    "mi", // Mini Heroes
    "fr", // Fast Respawn
    "so"  // Switch On
};

示例:

“DOTA AREMDM美国信用证”->“aremdm”

“DotA v6.60-美国ApEmDuSpId BL”->“Apemdupid”

笔记: 解决方案不一定要提供实际代码、伪代码,甚至只是解释如何处理它也是可以接受和首选的。此外,解决方案需要足够灵活,我可以添加另一个游戏模式相当容易。同样可以安全地假设,在游戏名称中,游戏模式始终以主游戏模式开始。

结果:

#include <cstdarg>
#include <algorithm>
#include <iostream>
#include <string>
#include <sstream>
#include <map>
#include <vector>

std::map<std::string, std::vector<std::string> > ModeCompatibilityMap;

static const unsigned int PrimaryModesCount = 11;
static char *PrimaryModes[] = { 
    "ap", "ar", "tr", "mr", "lm", "rd", "vr", "el", "sd", "cm", "cd"
};

static const unsigned int SecondaryModesCounts = 19;
static char *SecondaryModes[] = {
    "dm", "rv", "mm", "du", "sh", "aa", "ai", "as", "id", "em", "np",
    "sc", "om", "nt", "nm", "nb", "ro", "mo", "sp"
};

static const unsigned int MiscModesCount = 8;
static char *MiscModes[] = {
    "ns", "nr", "ts", "pm", "oi", "mi", "fr", "so" 
};

std::vector<std::string> Vectorize( int count, ... ) {
    std::vector<std::string> result;

    va_list vl;
    va_start( vl, count );

    for ( int i = 0; i < count; ++i ) {
        char *buffer = va_arg( vl, char * );
        result.push_back( buffer );
    }

    va_end( vl );

    return result;
}

void InitializeModeCompatibilityMap() {
    // Primary
    ModeCompatibilityMap["ar"] = Vectorize( 1, "rv" );
    ModeCompatibilityMap["tr"] = Vectorize( 2, "dm", "rv" );
    ModeCompatibilityMap["mr"] = Vectorize( 8, "dm", "rv", "sh", "aa", "ai", "as", "ro", "mo" );
    ModeCompatibilityMap["lm"] = Vectorize( 18, "dm", "rv", "mm", "du", "sh", "aa", "ai", "as", "id", "em", "np", "sc", "om", "nt", "nm", "nb", "ro", "mo" );
    ModeCompatibilityMap["rd"] = Vectorize( 9, "dm", "rv", "mm", "sh", "aa", "ai", "as", "ro", "mo" );
    ModeCompatibilityMap["vr"] = Vectorize( 9, "dm", "rv", "mm", "sh", "aa", "ai", "as", "ro", "mo" );
    ModeCompatibilityMap["el"] = Vectorize( 18, "dm", "rv", "mm", "du", "sh", "aa", "ai", "as", "id", "em", "np", "sc", "om", "nt", "nm", "nb", "ro", "mo" );
    ModeCompatibilityMap["sd"] = Vectorize( 9, "dm", "rv", "mm", "sh", "aa", "ai", "as", "ro", "mo" );
    ModeCompatibilityMap["cm"] = Vectorize( 19, "dm", "rv", "mm", "du", "sh", "aa", "ai", "as", "id", "em", "np", "sc", "om", "nt", "nm", "nb", "ro", "mo", "sp" );
    ModeCompatibilityMap["cd"] = Vectorize( 9, "dm", "rv", "mm", "sh", "aa", "ai", "as", "ro", "mo" );   
    // Secondary
    ModeCompatibilityMap["dm"] = Vectorize( 8, "rv", "mm", "sh", "aa", "ai", "as", "ro", "mo" );
    ModeCompatibilityMap["rv"] = Vectorize( 2, "dm", "sh" );
    ModeCompatibilityMap["mm"] = Vectorize( 2, "dm", "sh" );
    ModeCompatibilityMap["sh"] = Vectorize( 3, "dm", "rv", "mm" );
    ModeCompatibilityMap["aa"] = Vectorize( 3, "dm", "ai", "as" );
    ModeCompatibilityMap["ai"] = Vectorize( 3, "dm", "aa", "as" );
    ModeCompatibilityMap["as"] = Vectorize( 3, "dm", "aa", "ai" );
    ModeCompatibilityMap["ro"] = Vectorize( 2, "dm", "mo" );
    ModeCompatibilityMap["mo"] = Vectorize( 2, "dm", "ro" );
}

std::vector<std::string> Tokenize( const std::string &string ) {
    std::vector<std::string> tokens;
    std::string token;
    std::stringstream ss( string );

    while ( ss >> token ) {
        tokens.push_back( token );
    }

    return tokens;
}

void SanitizeString( std::string &in ) {
    std::transform( in.begin(), in.end(), in.begin(), tolower );

    for ( size_t i = 0; i < in.size(); ++i ) {
        if ( in[i] < 'a' || in[i] > 'z' ) {
            in.erase( i--, 1 );
        }
    }
}

std::vector<std::string> SplitString( const std::string &in, int count ) {
    std::vector<std::string> result;

    if ( in.length() % count != 0 ) {
        return result;
    }

    for ( std::string::const_iterator i = in.begin(); i != in.end(); i += count ) {
        result.push_back( std::string( i, i + count ) );
    }

    return result;
}

bool IsPrimaryGameMode( const std::string &in ) {
    for ( int i = 0; i < PrimaryModesCount; ++i ) {
        if ( strcmp( PrimaryModes[i], in.c_str() ) == 0 ) {
            return true;
        }
    }

    return false;
}

bool IsSecondaryGameMode( const std::string &in ) {
    for ( int i = 0; i < SecondaryModesCounts; ++i ) {
        if ( strcmp( SecondaryModes[i], in.c_str() ) == 0 ) {
            return true;
        }
    }

    return false;
}

bool IsMiscGameMode( const std::string &in ) {
    for ( int i = 0; i < MiscModesCount; ++i ) {
        if ( strcmp( MiscModes[i], in.c_str() ) == 0 ) {
            return true;
        }
    }

    return false;
}

bool IsValidGameMode( std::string in, std::string &out ) {
    // 1. Strip all non-letters from the string and convert it to lower-case
    SanitizeString( in );

    // 2. Confirm that it is a multiple of 2
    if ( in.length() == 0 || in.length() % 2 != 0 ) {
        return false;
    }

    // 3. Split the string further into strings of 2 characters
    std::vector<std::string> modes = SplitString( in, 2 );

    // 4. Verify that each game mode is a valid game mode and is compatible with the others
    bool primaryModeSet = false;

    for ( size_t i = 0; i < modes.size(); ++i ) {
        if ( IsPrimaryGameMode( modes[i] ) || IsSecondaryGameMode( modes[i] ) ) {
            if ( IsPrimaryGameMode( modes[i] ) ) {
                if ( primaryModeSet ) {
                    return false;
                }

                primaryModeSet = true;
            }

            if ( ModeCompatibilityMap.count( modes[i] ) > 0 ) {
                std::vector<std::string> badModes = ModeCompatibilityMap[modes[i]];

                for ( size_t j = 0; j < badModes.size(); ++j ) {
                    for ( size_t k = 0; k < modes.size(); ++k ) {
                        if ( badModes[j] == modes[k] ) {
                            return false;
                        }
                    }
                }
            }
        } else if ( !IsMiscGameMode( modes[i] ) ) {
            return false;
        }
    }

    // 5. Assign the output variable with the game mode and return true
    out = in;

    return true;
}

std::string ExtractGameMode( const std::string &gameName ) {
    std::vector<std::string> tokens = Tokenize( gameName );

    std::string gameMode;

    for ( size_t i = 0; i < tokens.size(); ++i ) {
        if ( IsValidGameMode( tokens[i], gameMode ) ) {
            return gameMode;
        }
    }

    return "";
}

int main( int argc, char *argv[] ) {
    InitializeModeCompatibilityMap();

    std::string gameName = "DotA v6.60 -RDEM USA/CA LC";
    std::string gameMode = ExtractGameMode( gameName );

    std::cout << "Name: " << gameName << std::endl;
    std::cout << "Mode: " << gameMode << std::endl;

    return 0;
}

名称:DotA v6.60-RDEM USA/CA LC

模式:rdem

如果有人想查看此代码,并让我知道他们将更改什么,我们将不胜感激。

谢谢

4 回复 | 直到 15 年前

Doug T. 15 年前

创建bool数组,该数组复制已放入注释中的表。除“X”或空白外,输入“真”或“假”(因此“真”表示模式组合有效,“假”表示无效)。

使用此表查找组合是否有效:

 bool IsSecondaryValidWithPrimary(unsigned int primaryIndex, unsigned int secondaryIndex)
 {
     static bool secondaryValidWithPrimary[numPrimaryModes][numSecondaryModes] = {...}

     if (primaryIndex < numPrimaryModes && secondaryIndex < numSecondaryModes)
     {
         return secondaryValidWithPrimary[primaryIndex][secondaryIndex]
     }
     else
     {
         //... this should never happen, throw your favorite exception
     }
 }

对其他有效性检查(二级与另一二级)或具有兼容性规则的任何其他模式组合执行相同的操作。

Dolphin 15 年前

我可以尝试将每个模式放入一个带有 白名单 横断下一个节点的白名单和工作白名单。继续,直到到达字符串末尾或白名单为空。如果白名单为空,并且您不在字符串末尾,则白名单无效,否则为好。

misc模式可能不属于白名单(因为它们在每个白名单上)。

您也可以尝试使用 黑名单 协会在每个步骤中,如果模式在列表中,则退出。

Game_Overture 15 年前

真正地 要避免给最终用户更多的规则,您可以尝试以下方法。。。

ToLower()整个游戏名称字符串。
使用空格“”分隔符拆分游戏名称。
分析每个单词,做以下操作。如果有什么失败,请转到下一个单词。

strcmp()将接下来的2个字符与每个主要游戏类型匹配,直到找到匹配的字符。否则失败并进入下一个单词。

这应该提取游戏类型,否则您可以责怪用户使用了错误的游戏名称。

现在,更难的部分是验证游戏类型是否相互兼容。我建议您创建一个结构,其中包含一个布尔数据结构,表示每种次要游戏类型。可以使用枚举访问的std::map或单个布尔数组。

现在需要一个数据对象来表示每个主要游戏类型也作为每个次要游戏类型。

然后只需为每种游戏类型制作一个数组,包括主要游戏类型和次要游戏类型。请参阅代码示例:

map<const char*, bool> mapSecondaryCompatibility;

struct tGameType
{
    char szName[3];
    mapSecondaryCompatibility m_compat;
}

正如你所看到的,从技术上讲,你的主要和次要游戏类型没有区别,它们都有相同的限制。。。可能与其他辅助游戏类型不兼容。

哦,我是DotA的超级粉丝。。。继续努力!

Kieveli 15 年前

在内部,我将创建一个std::map<int,std::vector<int>&燃气轮机;存储可兼容模式的列表。一旦输入命令行,我就会将这两个字符串转换为枚举值。然后我会在兼容模式映射中进行查找,看看它是否是允许的模式。

如何填充地图取决于您-我认为您可以有一个类来完成它-一个兼容性加载程序,或者如果希望最终用户能够修改可用模式,您可以从配置文件中驱动它。

使用枚举会更好,这样您就可以在编译时执行大量检查,而不是运行时检查。当从输入字符串转换为枚举时,执行一次运行时检查,如果无效,则向用户返回失败消息。然后在编译时检查所有其他代码。