Question

In C++

Sorted List of User Entered Numbers 2. Write a program that reads in a list of integers into a vector with base type int. Provide the facility to read this vector from an input file. Make sure to ask the user for a filename. The output is a two-column list. The first column is a list of the distinct vector elements. The second column is the count of the number of occurrences for each element. The list should be sorted on entries in the first column, largest to smallest For example, for the input: -12 -12 4 -12 2 2 -12 ..the output should be N Count 2 2.2 4 -12 4

Answer 1

#include<iostream>

#include<stdio.h>

#include<stdlib.h>

#include<fstream>

#include<vector>

#include<utility>

#include<algorithm>

using namespace std;

bool comparator( const std::pair<int, int> &left, const std::pair<int, int> &right )

{

   return ( left.first > right.first);

}

void CalculateFrequency(int *arr , int n )

{

vector< pair<int,int> > moves;

pair<int,int> position;

for(int i=0;i<n;++i){ //iterate through array

bool flag= false; //check if encounter duplicates

size_t x=0;

for ( ; x < moves.size(); ++x ) { //iterate the vector

   if(moves[x].first == arr[i]){

moves[x].second++;

flag = true;

break;

   }

}

if(!flag){

   position.first = arr[i];

   position.second = 1;

   moves.push_back(std::make_pair(position.first, position.second)); //Make pair i.e first element as array element and 2nd element as Count

}

}

sort(moves.begin() , moves.end(), comparator); //Sort the pair in descending order using comparator

cout << " N" <<" " << "Count" << endl;

   for ( size_t x = 0; x < moves.size(); ++x ) { //Print Output

printf(" %d\t%d\n",moves[x].first ,moves[x].second);

   }

}

int main ()

{

char choice;

while(true ) {

printf("Enter Your choice\n" ) ;

printf("1. Take input from the Keyboard\n");

printf("2. Take Input from the File\n");

printf("3. Exit\n" ) ;

scanf("%c",&choice);

string filename;

int n, count=0;

int *arr;

ifstream File;

switch(choice)

{

case '1' :

printf("Enter the number of elements\n");

scanf("%d",&n);

arr = (int *)malloc(n*sizeof(int));

for(int i=0;i<n;++i)

{

if(i==0)

printf("Enter %dst element: ", (i+1) );

else if(i==1)

printf("Enter %dnd element: ", (i+1) );

else if(i==2)

printf("Enter %drd element: ", (i+1) );

else

printf("Enter %dth element: ", (i+1) );

scanf("%d",&arr[i]);

}

CalculateFrequency(arr, n);

break;

case '2':

printf("Enter the name of file\n");

cin>>filename;

int a;

File.open(filename);

while (File >> a){

   ++count;

}

File.close();

File.open(filename);

arr = (int *)malloc(count*sizeof(int));

for(int a = 0; a < count; a++)

   File >> arr[a];

CalculateFrequency(arr, count);

break;

case '3':

exit(0);

break;

default:

printf("Wrong Choice\n");

}

}

return 0;

}
=================================================================================
Adding Images, Comments and Output for more clarity

Ξί nc Lude«iostream» rinc Lude«stdio.h> includeestdlib.h> #1 ncludeefs trean> #1 nclude<vector> #include«utility» rincludecalgorithn» using namespace std; bool conparator const std::paircint, int &left, const std: :paircint, int> &right) return left.first > right.first); void CalculateFrequency(int tarr, int n vector< paircint,int> > moves; paircint,int> position; for(int i-0;in;4+i) /iterate through array bool flag- false /check if encounter duplicates size t x- for x < moves.size): x Iiterate the vector İf (moves [x) . first arr[1]){ ,, noves [x].second++; flagtrue; break; if !flag) position.firstarr[i] position.second 1; moves. push-back(std: :nake-pair(position. first, position. second)); //Make pair ǐ.e first element as array elenent and 2nd element as Count sort noves.beginmoves.end), comparator); //Sort the pair in descending order using comparator " <c "Count" << endl; for ( size-t x-0; х< moves. size(); ++x } { //Print Output printf(" %d\ted\n" ,moves [x].first ,move s [x].second); int main) char choice; while(true printf("Enter Your choice\n" printf("1. Take input fron the Keyboardn"); printf("2. Take Input fron the File\n"); printf("3. Exitin" scan f ( "%c" , &choice) ; string filenane; intn, count-9; int tarr ifstrean File;

switch (choice) case '1': printf("Enter the number of elements\n"); scanf ("9sd", &n) arr- (int *)malloc(n*sizeof (int)); for(int i-0;i<n;++i) if(i--0) printf("Enter %d st element : else if(i--1) printf("Enter sdnd element: else if (i--2) printf("Enter %d rd element : else printf("Enter %d th element. scanf("%d" , &arr[i]); ", ", ", ", (1+1) ); (i+1)); (1+1) ); (1+1) ); CalculateFrequency (arr, n); break; case '2': printf("Enter the name of file\n") cin>>filename; int a; File.open(filename); while (File > a)1 ++count File.close(); File.open ( filename); arr - (int *)malloc(count*sizeof(int)); for(int a = 0; a count; a++) File >> arr[a]; CalculateFrequency (arr, count); break; case '3': exit(0); break; default: printf("Wrong Choice\n"); return 0; INSERT -- -
Output

RKUNDRA-M-M38W:~ rkundra$ ./a.ouft Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit Enter the number of elements Enter 1st element: 1 Enter 2nd element: 1 Enter 3rd element: 2 Enter 4th element: 2 Enter 5th element: 4 Count 4 Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit Enter the name of file filename.txt Count 4 1 12 Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit 4 Wrong Choice Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit RKUNDRA-M-M38W:~ rkundra$
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Attaching more Images


RKUNDRA-M-M38W:~ rkundraş vi frequency. cpp RKUNDRA-M-M38W:~ rkundra$ g++ frequency. cpp RKUNDRA-M-M38Wrkundra$ ./a.out Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit Enter the number of elements Enter 1st element:1 Enter 2nd element: 1 Enter 3rd element: 1 Enter 4th element: 2 Enter 5th element:3 Count Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit Enter the number of elements Enter 1st element: 3 Enter 2nd element: 3 Enter 3rd element: 3 Count Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit RKUNDRA-M-M38:~ rkundra$

RKUNDRA-M-M38W: rkundraş g++ frequency.cpp RKUNDRA-M-M38W:~ rkundra$ ./a.out Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit 2 Enter the name of file filename.txt Count 4 3 2 4 1 1 -12 4 Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit RKUNDRA-M-M38W:~ rkundra$

12 3 -12 4 11 -12 1 -1 1 2 3 4 2 3 -12 re re ne nd nd nd Ad re re "filename.txt" 1L, 41C




MORE RUNS


Files saved share run gcc version 4·6·3 Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit main.cpp main.cpp I #includeio stream» #include«stdio.h #include«stdlib.h> #include«fstream» Enter the number of elements 4 Enter 1st element: 1 Enter 2nd element: 1 Enter 3rd element: 2 5 7 N Count 2 9 #include«vector» 10 11 #include«utility» 12 13 #include«algorithm» 14 15 using namespace std; 16 17 bool comparator( const std::pair<int, int> &left, Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit Wrong Choice Enter Your choice 1. Take input from the Keyboard 2. Take Input from the File 3. Exit const std::pair<int, int> &right) 18 19 20 21 return left.first > right.first); 23 24


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