Hello everybody !
I'm a novice , and already started learn C++ . I try sorting string alphabetically from a text file . This is my code

#include <iostream> 
#include <fstream>

using namespace std;

// Quick Sort function
void quickSort(char A[][15], int lower, int upper){
    if (lower>=upper) return ;                // If first >= lastest -> not array ;
    int i=lower ; int j=upper;
    char *x;
    x=A[(lower+upper)/2];                     // middle point is pivot
    while(i<=j){
        while ((strcmp(A[i],x) < 0))          // Compare A[i] and pivot
          i++;
        while ((strcmp(A[j],x) > 0))
          j--;
        if(i<=j){                             // Swap A[i] , A[j]
            char tmp[20];
            strcpy(tmp,A[i]);                 // 
            strcpy(A[i],A[j]);
            strcpy(A[j],A[i]);
            i++;j--;
          }
      }
    if(j>lower){                              // Call recursion
      quickSort(A,lower,j);
      }
    if(i<upper){
      quickSort(A,i,upper);
      }
  }

main(){
   int k=0,n=0;char array[100][15];  
   ifstream in("quicksort.in");               // Call input file
   ofstream out("quicksort.out");             // Call output file
  
  in>>n;int l=0;                              // The first number is height of array
  
  for(k=0;k<n;++k){                           // insert data into array
      while(array[k][l]!=NULL){               // insert each character into two-dimensional array
            in>>array[k][l];
            l++;
        }
    }
  in.close();                               
  quickSort(array,0,n-1);                     // Call quicksort
  
  for(k=0;k<n;++k){                           // Export to output
          out<<array[k]<<"\n";                           
    }
  out.close(); 
  system( "pause" );
}

Form of input file like
3
nga
born
hell

But output don't like I image . Anybody help me ? Thank so much.

If it's a file of simple words, why not just in>>array[k]; rather than trying to read (poorly) one character at a time.

If it's a file of simple words, why not just in>>array[k]; rather than trying to read (poorly) one character at a time.

I wrote QuickSort function with input is two-dimensional array A[][] . And I think import data from text file into array[][] with

#
for(k=0;k<n;++k){ 
while(array[k][l]!=NULL){

in>>array[k][l];

l++;

}

}

Before sorting it, just read it in, then print it out.

Until that works, don't waste effort trying to debug a sort function with garbage data.

Before sorting it, just read it in, then print it out.

Until that works, don't waste effort trying to debug a sort function with garbage data.

Thnx so much , i try and it works.
But I have another question . In input file , i have some int value .
Like that
3
4
5
2
I want to compare them in same Quicksort function. Any body help ?

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