[컴파일러개론 실습] 1. 엄랭 to C 컴파일러

import java.io.*;

public class Main {
    static String Calculate(String s,  String var) {
        StringBuilder sb = new StringBuilder();
        int N = s.length();

        s += '#';
        
        sb.append('(').append('0');
        for (int i = 0; i < N; i++) {
            char c = s.charAt(i);
            if (c == '.') {
                sb.append("+1");
            } else if (c == ',') {
                sb.append(-1);
            } else if (c == ' ') {
                sb.append(")*(");
            } else if (c == '식') {
                ++i;
                sb.append('+').append(var);
            } else if (c == '어') {
                char next = s.charAt(i+1);
                if (next == '어') continue;
                int idx = 0;
                if (i > 0 && s.charAt(i-1) == '어') {
                    ++idx;
                    if (i > 1 && s.charAt(i-1) == '어') {
                        ++idx;
                    }
                }
                sb.append('+').append("arr[").append(idx).append(']');
            } else {
                // Do nothing
            }
        }
        sb.append(')');

        return sb.toString();
    }

    static String Printf(String s, char fmt) {
        if (fmt == 'ㅋ') fmt = 'c';
        else fmt = 'd';

        return "\tprintf(\"%"+fmt+"\", " + Calculate(s, "") + ");\n";
    }

    static String Scanf(String var) {
        return "\tscanf(\"%d\", &" + var + ");\n";
    }

    static String Um(String var, String s) {
        String sik = "";
        if (s.contains("식?")) sik = Scanf(var);
        
        return sik + '\t' + var + " = " + Calculate(s, var) + ";\n";
    }

    public static void main(String[] args) throws IOException {
        File umf = new File("./test.umm"), cf = new File("./test.c");
        BufferedReader br = new BufferedReader(new FileReader(umf));
        BufferedWriter bw = new BufferedWriter(new FileWriter(cf));

        bw.write("#include <stdio.h>\n\n");
        bw.write("int main() {\n");
        bw.write("\tint arr[3];\n");
        bw.write("\tarr[0] = 0; ");
        bw.write("arr[1] = 0; ");
        bw.write("arr[2] = 0;\n\n");

        String s;
        while ((s = br.readLine()) != null) {
            if (s.equals("어떻게") || s.equals("이 사람이름이냐ㅋㅋ")) continue;

            int N = s.length();
            if (s.contains("엄")) {
                int idx = s.charAt(0) == '엄' ? 0 : s.charAt(1) == '엄' ? 1 : 2;
                bw.write(Um("arr["+idx+"]", s.substring(idx+1, N)));
            } else if (s.contains("식")) {
                bw.write(Printf(s.substring(1, N-1), s.charAt(N-1)));
            } else {
                // Do nothing
            }
        }

        bw.write("\n\treturn 0;\n");
        bw.write("}");

        bw.flush();
        bw.close();
        br.close();
    }
}