Frame Sorting

//Write a program for frame sorting technique used in buffers.

#include<bits/stdc++.h>
using namespace std;

struct packet{
    string str;
    int num;
};

int main(){
    struct packet s1[100],s2[100],s3[100];
    int cnt = 0;
    cout << "Enter The message to be Transmitted :\n";
    string s;
    getline(cin,s);
    cout << "\nEnter the size of the frame\n";
    int frame;
    cin >> frame;
    for(int i = 0 ; i < s.size(); i+=frame){
        string x;
        for(int j = i ; j < i+frame; j++){
            x+=s[j];
        }
        s1[cnt].str = x;
        s1[cnt].num = cnt;
        cnt++;
        x.clear();
    }
    cout << "\nBefore shuffle\n";
    for(int i = 0 ; i < cnt; i++){
        cout << s1[i].num << " " << s1[i].str << endl;
    }
    int data[cnt];

    for(int i = 0; i < cnt; i++){
        data[i] = i;
    }

    random_shuffle(data,data+cnt);

    //s2 struct to carry shuffled values

    for(int i = 0 ; i < cnt; i++){
        s2[data[i]].num = s1[i].num;
        s2[data[i]].str = s1[i].str;
    }

    cout << "\nafter shuffle\n";
    //after shuffle
    for(int i = 0 ; i < cnt; i++){
        cout << s2[i].num << " " << s2[i].str << endl;
    }
    for(int i = 0 ; i < cnt; i++){
        int x = INT_MAX,j=0,index = 0;
        for(j = 0; j < cnt; j++){
            if(s2[j].num < x && s2[j].num<INT_MAX){
                x = s2[j].num;
                index = j;
            }
        }
        s3[i].num = x;
        s3[i].str = s2[index].str;
        s2[index].num = INT_MAX;
    }
    cout << "\nMessage received is :\n";
    for(int i = 0 ; i < cnt; i++){
        cout << s3[i].str;
    }
    cout << endl;
}

/*
OUTPUT


Enter The message to be Transmitted :
nmamit nitte

Enter the size of the frame
3

Before shuffle
0 nma
1 mit
2  ni
3 tte

after shuffle
0 nma
2  ni
3 tte
1 mit

Message received is :
nmamit nitte




*/