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AdmiinX/Compiler.cpp

Created April 27, 2015 21:49
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  1. AdmiinX created this gist Apr 27, 2015.
    143 changes: 143 additions & 0 deletions Compiler.cpp
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,143 @@
    //============================================================================
    // Task : Compiler
    // Description : Lexical Analyzer
    // Name : Mahmoud Mohamed Fathy
    // ID : 2012030135
    //============================================================================

    #include <iostream>
    #include <fstream>
    #include <string>
    using namespace std;

    const string reservedWords[] = { "include", "iostream", "namespace", "using",
    "std", "void", "main", "int", "float", "char", "string" };
    const char alphabets[] = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
    'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
    'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L',
    'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
    const char numbers[] = { '1', '2', '3', '4', '5', '6', '7', '8', '9', '0' };
    const char operators[] = { '+', '-', '*', '/', '%' };
    const char specialSymbols[] ={';','{','}','(',')','=','\'','\"','<','>','#',',','!','.'};

    bool isIdentifier(string word) {
    int counter = 0;
    for (int i = 0; i < word.size(); i++) {
    if (i == 0) {
    for (int j = 0; j < sizeof(alphabets); j++) {
    if (word.at(i) == alphabets[j]) {
    counter++;
    break;
    }
    }
    }
    else {
    for (int j = 0; j < sizeof(alphabets); j++) {
    if (word.at(i) == alphabets[j]) {
    counter++;
    goto end_else;
    }
    }
    for (int k = 0; k < sizeof(numbers); k++) {
    if (word.at(i) == numbers[k]) {
    counter++;
    }
    }
    end_else: ;
    }
    }
    if (counter == word.size())
    return true;
    return false;
    }

    bool isInteger(string word) {
    int counter = 0;
    for (int i = 0; i < word.size(); i++) {
    for (int j = 0; j < sizeof(numbers); j++) {
    if (word.at(i) == numbers[j]) {
    counter++;
    break;
    }
    }
    }
    if (counter == word.size())
    return true;
    return false;
    }

    bool isReservedWord(string word) {
    for (int i=0;i<sizeof(reservedWords)/sizeof(reservedWords[i]);i++) {
    if (word == reservedWords[i])
    return true;
    }
    return false;
    }

    bool isOperator(string word) {
    for (int i = 0; i < sizeof(operators); i++) {
    if (word.at(0) == operators[i])
    return true;
    }
    return false;
    }

    bool isSpecialSymbols(string word) {
    int counter = 0;
    for (int j = 0; j < sizeof(specialSymbols); j++) {
    if (word[0] == specialSymbols[j])
    return true;
    }
    return false;
    }

    int main() {
    ifstream myfile;
    string word;
    string previousWord;

    myfile.open("code.txt");
    while (!myfile.eof()) {
    myfile >> word;
    if (previousWord == "integer") {
    if (isOperator(word)) {
    cout << word << "\tis arithmetic operator\n";
    previousWord = "operator";
    } else {
    goto startOfElse;
    }
    }
    else if (previousWord == "operator") {
    if (isInteger(word)) {
    cout << word << "\tis Integer\n";
    previousWord = "integer";
    } else {
    cout<<word<<"\tError in position "<<myfile.tellg()<< " not integer after operator" << endl;
    goto startOfElse;
    }
    }
    else {
    startOfElse: if (isInteger(word)) {
    cout << word << "\tis Integer\n";
    previousWord = "integer";
    } else if (isReservedWord(word)) {
    cout << word << "\tis ReservedWord\n";
    previousWord = "reservedWord";
    } else if (isIdentifier(word)) {
    cout << word << "\tis Identifier\n";
    previousWord = "Identifier";
    } else if (isSpecialSymbols(word)) {
    cout << word << "\tis SpecialSymbols\n";
    previousWord = "SpecialSymbols";
    } else if (isOperator(word) && previousWord != "integer") {
    cout<<word<<"\tError in position "<<myfile.tellg()<<" not integer before operator";
    cout << word << "\tis arithmetic operator\n";
    previousWord = "operator";
    } else {
    cout<<word<<"\tError in position "<<myfile.tellg()<<" could not be resolved"<<endl;
    previousWord = "";
    }
    }
    }
    return 0;
    }
    9 changes: 9 additions & 0 deletions code.txt
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,9 @@
    # include < iostream >
    using namespace ;
    void main ( ) {
    int result ;
    result = 321 + 123 ;
    50 + 20 + 874 + 123h32 ;
    int result2 = 764 + 259 + void ;
    786das
    }