c++ - Getting Memory error while sorting pairs. Can anybody tell me where am i going wrong in the code -

i trying sort pairs (struct pairs { int i; int j; } ) value of i. after sorting store pairs according has highest number of j's corresponding it. (1,3),(1,4),(2,5),(2,6),(2,7). have structure els(int *i,int *j,int count),els[0] should have 2,5,,2,6,,2,7,,where 2's stored in i,5,6,7 in j.els[1] have 1, correspondings. in structure els when using pairs structure code os running fine,but when going 2 individual arrays i,j getting assert() coredumped error.

#include<iostream> #include<time.h> #include<stdio.h> #include<math.h> #include<stdlib.h> struct pairs {     int i;     int j; }; struct els {         int *i;     int *j;     int count; }; void sortpairs(struct pairs *p,int count); void sortj(struct pairs *p,int count); void swapp(struct pairs *p,struct pairs *q); int random(int min,int max); int elina(int el,int arr[],int siz);  int main() {     struct pairs *pp = new struct pairs[10];     srand(time(0));     for(int = 0;i<10;i++)     {         pp[i].i = random(0,10);         pp[i].j = random(0,10);     }     std::cout <<"before\n";     for(int = 0;i<10;i++)     {         std::cout << pp[i].i <<"       "<<pp[i].j<<"\n";     }     sortj(pp,10);     std::cout << "done sorting\n";     std::cout <<"after\n";     for(int = 0;i<10;i++)     {         std::cout << pp[i].i <<"       "<<pp[i].j<<"\n";     }     sortpairs(pp,10);       return 0; }  void swapp(struct pairs *p,struct pairs *q) {     struct pairs temp;     temp = *p;     *p = *q;     *q = temp; }  int random(int min,int max) {     int n;     n = rand()%(max - min) + min;     return n; }  int elina(int el,int arr[],int siz) {     for(int = 0 ;i < siz;i++)     {         if(arr[i] == el)             return i;     }     return -9; }  void sortj(struct pairs *p,int count) { for(int = 0 ; < count - 1;i++)     for(int j = + 1;j < count;j++)     {         if(p[i].i > p[j].i)             swapp(&p[i],&p[j]);     } }  void sortpairs(struct pairs *p,int count) {     int *arr = new int[count];     int unqc = 0,az = 0,t;     int  i;     for(i = 0; i< count ;i++)     {         arr[i] = p[i].i;         if(t = elina(arr[i],arr,i) < 0)             unqc++;     }     az = i;     std::cout <<"the unique elements "<<unqc<<"\n";     struct els *e = new struct els[unqc];     int ec = 0;     //e[0].i = new struct pairs[10];     e[0].i = new int[10];     e[0].j = new int[10];     e[0].count = 0;     for(int j = 0 ; j < count;j++)       {         if(j > 0)         {             if(p[j].i == p[j-1].i)             {             //e[ec].p[count].i = p[j].i;             //e[ec].p[count].j = p[j].j;             e[ec].i[count] = p[j].i;             e[ec].j[count] = p[j].j;             e[ec].count++;             }             else             {             ec++;             //e[ec].p = new struct pairs[10];             e[ec].i = new int[10];             e[ec].j = new int[10];             e[ec].count = 0;             //e[ec].p[count].i = p[j].i;             //e[ec].p[count].j = p[j].j;             e[ec].i[count] = p[j].i;             e[ec].j[count] = p[j].j;             e[ec].count++;             }         }         else         {             //e[ec].p[count].i = p[j].i;             //e[ec].p[count].j = p[j].j;             e[ec].i[count] = p[j].i;             e[ec].j[count] = p[j].j;             e[ec].count++;         }     }     for(int j = 0 ; j < unqc;j++)     {         std::cout << e[j].count <<"\n";     } } 

in various places

        e[ec].i[count] = p[j].i;         e[ec].j[count] = p[j].j; 

should be

        e[ec].i[e[ec].count] = p[j].i;         e[ec].j[e[ec].count] = p[j].j; 

if had used std::vector instead of new have found code easier write, , have fewer bugs , limitations.