test of ignoring // cpp-style comments in c-style */

using namespace std; int main() {

/* the test of comment with null length */ /* */

/* test of cpp-style comment // inside another cpp-style comment // */

cout << " 9 // 2 =

" << 9 / 2 << endl; /* test of ingoring // in strings */ return 0;

} /* end */ Success!

Текст программы

#include <stdio.h> #include <stdlib.h> #include <string.h>

#define MAXLEN 256

#if defined(_WIN32) || defined(WIN32) || defined(WINNT) || defined(MSVC) #define clear_console() system("cls")

#else

#define clear_console() system("clear") #endif

/* Arguments: buffer - allocated buffer of chars,

*Return value: size of data in the buffer.

*Purpose: reads lines from the console to the given buffer,

*until the user enters the specified string. */

size_t read_from_console(char *buffer, size_t size, char *last_str);

/* Arguments: buffer - allocated buffer of chars,

*Return value: size of data in the buffer.

*Purpose: reads a text (data without zeros) to the given buffer from the file. */

size_t read_from_file(char *buffer, size_t size, FILE* file);

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/* Arguments: n - length of the line, * c - char for printing.

* Purpose: prints a line of given chars to the console. */ void print_line_of_chars(size_t n, char c);

/* Arguments: buffer - pointer to the string.

* Purpose: prints text to the console and underlines comments. */

clear_console(); puts(",---------------------------------------,");

puts("'---------------------------------------'\n");

puts("Source: file or console? Default: console"); fgets(input_str, MAXLEN, stdin); input_str[strlen(input_str) - 1] = '\0';

if (input_str[0] == '\0' || strcmp(input_str, "console") == 0) { strncpy(input_str, "console", MAXLEN);

input = stdin;

} else if (strcmp(input_str, "file") == 0) { puts("Enter a name of the file:"); fgets(input_str, MAXLEN, stdin); input_str[strlen(input_str) - 1] = '\0';

if ((input = fopen(input_str, "r")) == NULL)

printf("File \"%s\" does not exist or cannot be readed!\n", input_str);

} else

printf("\"%s\": unknown source type!\n", input_str);

if (input != NULL) {

puts("Destination: file or console? Default: console");

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fgets(output_str, MAXLEN, stdin); output_str[strlen(output_str) - 1] = '\0';

if (output_str[0] == '\0' || strcmp(output_str, "console") == 0) { strncpy(output_str, "console", MAXLEN);

output = stdout;

} else if (strcmp(output_str, "file") == 0) { puts("Enter a name of the file:"); fgets(output_str, MAXLEN, stdin); output_str[strlen(output_str) - 1] = '\0';

if ((output = fopen(output_str, "w")) == NULL)

printf("File \"%s\" cannot be created or used for writing!\n", output_str);

} else

printf("\"%s\": unknown destination type!\n", output_str);

if (output != NULL) { clear_console();

size = MAXLEN * MAXLEN; text = (char *)malloc(size);

if (text != NULL) {

if (input == stdin) {

puts("Enter the text and type string \"\\q\" to continue:"); size = read_from_console(text, size, "\\q\n"); clear_console();

} else

size = read_from_file(text, size, input);

if (size > 0) {

text = (char *)realloc(text, size); printf("Input: %s\n", input_str); printf("Output: %s\n", output_str);

puts("Analysis (\"~\" - comments for replacement):\n"); print_analysis(text);

puts("\nEnter any key to continue..."); getchar();

clear_console(); puts("Writing result...\n"); write_result(text, output); puts("\nSuccess!");

} else

printf("Warning: zero-sized buffer, please check its initial

size\n");

free(text); text = NULL;

} else

puts("Memory allocation error!");

if (output != stdout) fclose(output);

}

if (input != stdin)

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fclose(input);

}

puts("Try again? (y/n)"); fgets(input_str, MAXLEN, stdin);

} while (input_str[0] == 'y' || input_str[0] == 'Y' || input_str[0] == '\n');

return 0;

}

size_t read_from_console(char *buffer, size_t size, char *last_str) { char *c;

char temp[MAXLEN]; size_t res_size; res_size = 0;

if (size > 0) {

while (res_size < size && strcmp(fgets(temp, MAXLEN, stdin), last_str)) {

for(c = temp; *c && res_size < size; res_size++, c++) buffer[res_size] = *c;

}

if (res_size == size) buffer[size - 1] = '\0';

else

buffer[res_size++] = '\0';

}

return res_size;

}

size_t read_from_file(char *buffer, size_t size, FILE* file) { size_t res_size;

res_size = 0; if (size > 0) {

res_size = strnlen(buffer, fread(buffer, 1, size, file)); if (res_size == size)

buffer[size - 1] = '\0'; else

buffer[res_size++] = '\0';

}

return res_size;

}

void print_line_of_chars(size_t n, char c) { size_t i;

for (i = 0; i < n; i++) putchar(c);

}

void print_analysis(char *buffer) {

char last_c, is_cpp_style, is_c_style, is_string; char *c, *line_start, *comment_start; is_cpp_style = 0;

is_c_style = 0; is_string = 0;

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last_c = 0;

for (line_start = c = buffer; *c; c++) { if (*c == '\n') {

if (is_cpp_style) { is_cpp_style = 0; putchar('\n');

print_line_of_chars(comment_start - line_start, ' '); print_line_of_chars(c - comment_start, '~');

}

line_start = c + 1;

} else if (is_c_style) {

if (last_c == '*' && *c == '/') is_c_style = 0;

} else if (!is_cpp_style) { if (*c == '\"')

is_string = 1 - is_string;

else if (!is_string && last_c == '/') { if (*c == '/') {

is_cpp_style = 1; comment_start = c;

} else if (*c == '*') is_c_style = 1;

}

}

putchar(*c); last_c = *c;

}

if (is_cpp_style) { putchar('\n');

print_line_of_chars(comment_start - line_start, ' '); print_line_of_chars(c - comment_start, '~');

}

}

void write_result(char *buffer, FILE *file) {

char last_c, is_cpp_style, is_c_style, is_string, need_to_print; char *c;

is_cpp_style = 0; is_c_style = 0; is_string = 0; last_c = 0;

for (c = buffer; *c; c++) { need_to_print = 1;

if (is_c_style) {

if (last_c == '*' && *c == '/') is_c_style = 0;

}else if (is_cpp_style) { if (*c == '\n') {

need_to_print = 0; is_cpp_style = 0; fputs(" */\n", file);

}

}else {

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