quine

quine.c

#include <stdio.h>

static const char code[] =
    "#include <stdio.h>\n"
    "\n"
    "static const char code[] =\n"
    "    \"\0\";\n"
    "\n"
    "int main(void) {\n"
    "  for (size_t i = 0; i < sizeof(code) - 1; i++) {\n"
    "    if (code[i] == '\\0') {\n"
    "      for (size_t j = 0; j < sizeof(code) - 1; j++) {\n"
    "        if (code[j] == '\\0')\n"
    "          printf(\"\\\\0\");\n"
    "        else if (code[j] == '\\\\')\n"
    "          printf(\"\\\\\\\\\");\n"
    "        else if (code[j] == '\"')\n"
    "          printf(\"\\\\\\\"\");\n"
    "        else if (code[j] == '\\n')\n"
    "          printf(\"\\\\n\\\"\\n    \\\"\");\n"
    "        else\n"
    "          putchar((unsigned char) code[j]);\n"
    "      }\n"
    "    } else {\n"
    "      putchar((unsigned char) code[i]);\n"
    "    }\n"
    "  }\n"
    "  return 0;\n"
    "}\n"
    "";

int main(void) {
  for (size_t i = 0; i < sizeof(code) - 1; i++) {
    if (code[i] == '\0') {
      for (size_t j = 0; j < sizeof(code) - 1; j++) {
        if (code[j] == '\0')
          printf("\\0");
        else if (code[j] == '\\')
          printf("\\\\");
        else if (code[j] == '"')
          printf("\\\"");
        else if (code[j] == '\n')
          printf("\\n\"\n    \"");
        else
          putchar((unsigned char) code[j]);
      }
    } else {
      putchar((unsigned char) code[i]);
    }
  }
  return 0;
}