Extract data from text file in formatted/sequential way - c++

Question

I have a file .txt with this structure:
000010109000010309000010409
Where i need to read like this:
00001 01 09
00001 03 09
00001 04 09
I have a structure in this way:
struct A{
string number // first 5 numbers
int day; // 2 numbers
int month; // last 2 numbers
};
I tried in this way.
But dont work.
char number[6];
char day[3];
char monthes[3];
ifstream read("file.txt");
for (int i = 0; i < 100; i++) {
read.get(number,6);
structure[i].number= number;
read.get(day,3);
structure[i].day= atoi(day);
read.get(month,3);
structure[i].month= atoi(month);
}
How read and store the datas from the file to this structure?
And how compare if the number have in the same month many days.
Thanks a lot.

Answer 1

You could try something like this:
FILE *fp = fopen("file.txt", "r");
A a;
char x[6], y[3], z[3];
fscanf(fp, "%5s%2s%2s", x, y, z);
a.number = string(x);
a.day = atoi(y);
a.month = atoi(z);
EDIT:
It is valid C++ code (with cstdio and cstdlib), but if you want some C++ version, you could try something like this
// read from file.txt
std::ifstream inFile("file.txt", std::ios::in);
char number[6], day[3], month[3];
int cnt = 0;
while (inFile.get(number, 6) && inFile.get(day, 3) && inFile.get(month, 3)) {
// Let's assume that structure[] is array of struct A
structure[cnt].number = number;
structure[cnt].day = atoi(day);
structure[cnt].month = atoi(month);
++cnt;
}
// store to file2.txt
std::ofstream outFile("file2.txt", std::ios::out);
for (int i = 0; i < cnt; ++i) {
outFile << structure[i].number << ' ' << structure[i].day << ' ' << structure[i].month << std::endl;
// If you need fixed-width for day/month, use std::setw and std::setfill
}
// compare first two
if (cnt >= 2) {
if (structure[0].number == structure[1].number &&
structure[0].month == structure[1].month &&
structure[0].day == structure[1].day) {
std::cout << "Same!" << std::endl;
} else {
std::cout << "Different!" << std::endl;
}
}

Answer 2

I'm using stringstream here as an example but the same will work with fstream. Convert number, day and month from char arrays to required data types as necessary (all are '\0' terminated)
#include <iostream>
#include <sstream>
int main() {
std::string s = "000010109000010309000010409";
std::istringstream iss(s);
char number[6], day[3], month[3];
while (iss.get(number, 6) && iss.get(day, 3) && iss.get(month, 3))
std::cout << number << " " << day << " " << month << std::endl;
return 0;
}
https://ideone.com/tyBShW
00001 01 09
00001 03 09
00001 04 09