Splitting char array - c++

Question

I have a char **names array that basically stores names from a file.
This is my .txt file
Mike, Sam, Stuart
Andre, Williams, Phillips
Patels, Khan, Smith
Basically, I want to split and store the names before the , character.
For example, Mike, Sam, Stuart will become...
newName[0] = Mike
newName[1] = Sam
newName[2] = Stuart
I have something like this...
for (int i=0; i<3; i++)
{
for (int j=60, j>0; j--)
{
if(names[i][j] == ',')
{
cout << j << endl; //THIS PRINTS OUT THE POSITION. HOW CAN I STORE THE POSITION AND DO SOMETHING?
}
}
}
I would appreciate it if someone could help me with my code, it is in the right direction. I don't want to use any vectors classes
I have attempted to store marks of these students, however I want to add it to a double *marks[2] array.
This is my .txt file...
69.9, 56.5
29.8, 20.0
35.6, 45.0
This is my code...
char **values;
char * pch;
pch = strtok (values[i], " ,");
while (pch != NULL)
{
sscanf(pch, "%f, %f", &marks[i][0], &marks[i][1]);
pch = strtok (NULL, " ,");
}
I am getting random values such as 1.28277e-307 and 1.96471e+257

Answer 1

look up the strtok command it will be very helpful to you.
This code looks for hyphen characters and prints stuff... change it to commas
#include <string.h>
#include <stdio.h>
int main()
{
const char str[80] = "This is - www.tutorialspoint.com - website";
const char s[2] = "-";
char * newName[100]; /* at most 100 names */
int iCurName = 0;
char *token;
/* get the first token */
token = strtok(str, s);
/* walk through other tokens */
while( token != NULL )
{
printf( " %s\n", token );
newName[iCurName] = malloc (char *) (strlen(token) + 1);
strcpy(newName[iCurName],token);
iCurrName ++;
token = strtok(NULL, s);
}
return(0);
}

Answer 2

Use function strtok() to split input line into tokens; use strcpy_s() to copy each token into name buffer.
Note 1: The strtok() function replaces each separator with '\0' character, so the line variable cannot be declared with const. If your input buffer must be constant, for example if you want to use the whole line for something else, make a copy of it before calling strtok() function.
Note 2: You might want to trim space in addition to splitting your input line.
#define MAX_LINE_LENGTH 80
#define MAX_NAME_LENGTH 20
#define MAX_NAMES_PER_LINE 3
const char constInput = "Mike, Sam, Stewart";
char line[MAX_LINE_LENGTH];
strcpy_s(line, MAX_LINE_LENGTH, constInput);
char *separator = ",";
char newName[MAX_NAMES_PER_LINE][MAX_NAME_LENGTH];
int i = 0;
char *token = strtok(line, separator);
while ((i < MAX_NAMES_PER_LINE) && ((token = strtok(NULL, separator)) != NULL))
{
strcpy_s(newName[i++], MAX_NAME_LENGTH, token);
}

Answer 3

char newName[3][60];
for (int i=0; i<3; i++){
int r=0, c=0;
for (int j=0; j<60; j++){
if(names[i][j] == ',' || names[i][j] == '\0'){
newName[r++][c] = '\0';
c = 0;
if(names[i][j] == '\0'){
cout << newName[0] << '\n'
<< newName[1] << '\n'
<< newName[2] << '\n' << endl;
break;
}
while(names[i][++j] == ' ')
;
--j;
} else {
newName[r][c++] = names[i][j];
}
}
}
#include <fstream>
#include <iostream>
using namespace std;
int main() {
ifstream inf("data.txt");
double marks[2];
char ch;
while(inf.good()){
inf >> marks[0] >> ch >> marks[1];
cout << "mark1:" << marks[0] << endl;
cout << "mark2:" << marks[1] << endl;
}
}

Answer 4

I don't know if this function works fast enough, but here it is:
char** split_quotes(char *input, char separator = ' ', bool keep_quotes = false)
{
if (&input && input)
{
size_t length = strlen(input);
char **chunks = new char*[length];
bool inQuotes = false;
size_t count = 0, from = 0;
for (size_t i = 0; i < length; i++)
{
if (input[i] == '"')
{
inQuotes = !inQuotes;
}
else if (input[i] == separator && !inQuotes)
{
size_t strlen = i - from;
if (strlen > 0)
{
if (!keep_quotes && input[from] == '"' && input[i - 1] == '"')
{
from++; strlen -= 2;
}
chunks[count] = new char[strlen + 1]();
strncpy(chunks[count], &input[from], strlen);
count++;
}
from = i + 1;
}
}
if (from < length)
{
size_t strlen = length - from;
if (!keep_quotes && input[from] == L'"' && input[length - 1] == L'"')
{
from++; strlen -= 2;
}
chunks[count] = new char[strlen + 1]();
strncpy(chunks[count], &input[from], strlen);
count++;
}
// Save chunks to result array //
char **result = new char*[count + 1]();
memcpy(result, chunks, sizeof(char*) * count);
// free chunks //
delete[] chunks;
return result;
}
return NULL;
}
Usage:
wchar_t **name = split_quotes(L"Mike,Donald,\"My Angel\",Anna", L',');
if (name)
{
while (*name++)
{
std::wcout << "Person: " << *name << std::endl;
}
}