**Convert a string array with special character to an int array. Inputs are from a file**-CodePudding

My problems here is to take all the integers in the file, and stores to an int array( of course without '|'), and then do something with it( here I just need help to print out the array). The data from file is said to be a 10x10 matrix. My code output is another 10x10 with trash values as I tried std::stringstream

Input:

1|11|2|13|2|2|2|11|13|2
1|11|2|13|2|2|2|13|2|11
1|13|1|13|2|2|2|2|2|2
1|13|1|12|2|2|2|2|2|2
1|13|1|13|1|2|2|2|2|2
1|13|1|13|1|1|2|2|2|2
1|13|1|13|1|1|1|2|2|2
1|13|1|13|1|1|1|1|2|2
1|13|1|13|1|1|1|1|1|2 
1|13|1|13|1|1|1|1|1|1

Code:

#include<iostream>
#include<cstring>
#include<fstream>
#include<sstream>
using namespace std;
int main(){
    //read data from file and store in a 2d array
    ifstream myfile("input.txt");
    string arr[10][20];
    for(int i=0;i<10;i  ){
        for(int j=0;j<20;j  ){
            getline(myfile,arr[i][j],'|');
        }
    }
    //convert string to int
    //use stringstream
    int arr2[10][20];
    for(int i=0;i<10;i  ){
        for(int j=0;j<20;j  ){
            stringstream ss;
            ss<<arr[i][j];
            ss>>arr2[i][j];
        }
    }
    //print arr2
    for(int i=0;i<10;i  ){
        for(int j=0;j<20;j  ){
            cout<<arr2[i][j]<<" ";
        }
        cout<<endl;
    }
    myfile.close();
    return 0; 
    
}

The output should be:

1 11 2 13 2 2 2 11 13 2
1 11 2 13 2 2 2 13 2 11
1 13 1 13 2 2 2 2 2 2
1 13 1 12 2 2 2 2 2 2
1 13 1 13 1 2 2 2 2 2
1 13 1 13 1 1 2 2 2 2
1 13 1 13 1 1 1 2 2 2
1 13 1 13 1 1 1 1 2 2
1 13 1 13 1 1 1 1 1 2 
1 13 1 13 1 1 1 1 1 1

My output:

1 11 2 13 2 2 2 11 13 2 
1 13 2 2 2 2 2 2 13 1 
1 2 2 2 2 2 13 1 13 1 
1 2 2 2 13 1 13 1 1 1 
1 2 13 1 13 1 1 1 1 1 
1994842136 12 7086696 7085352 1994774642 0 1994842144 1994771436 0 0 
6416848 2004213955 7086772 6416972 12 7086696 0 4 48 1994842112 
2004213726 1 7149280 7149288 7086696 0 1988425164 0 2003400672 12 
1999860416 6416972 2 1999966512 1999657456 1999691632 1999846272 1999845632 1999819744 1999860464 
4194304 1994719472 0 6417024 0 6418312 2004471984 775517426 -2 6417120

CodePudding user response：

Two issues: You try to read 10x20 when there is only 10x10 in the file. Further your code assumes that there is a | between all adjacent numbers, but thats not the case. There is no | between the last number in a line and the first in the next line.

Change the size accordingly and read full lines before you split them at |:

string arr[10][10];
for(int i=0;i<10;i  ){
    std::string line;
    getline(myfile,line);
    std::stringstream linestream{line};
    for(int j=0;j<10;j  ){
        getline(linestream,arr[i][j],'|');
    }
}

Live Demo

This is minimum changes on your code. Next I would suggest to extract integers from the stream directly instead of first extracting string and then convert them to integers (by placing the strings into another stream and then extracting the integer, you could do this already with the ifstream).