Well, this one turned out to be easy. Luckily there is a function in the header algorithm (stable_sort) that sorts the objects on the basis of one of its contents ! and that's all was needed here !

Try to think how to solve it without any sorting!!!

without ANY sorting? How do you sort array without any sorting?

It is not necessary to sort array :) Just read input + :)

#include <cstdio>
#include <algorithm>

using namespace std;

struct node {
    int id;
    int solve;
} a [10000000 + 10];

bool cmp (node p, node q)
{
    if ( p.solve > q.solve ) return true;
    return false;
}

int main ()
{
    int n; scanf ("%d", &n);

    for ( int i = 0; i < n; i++ ) scanf ("%d %d", &a [i].id, &a [i].solve);

    stable_sort (a, a + n, cmp);

    for ( int i = 0; i < n; i++ ) printf ("%d %d\n", a [i].id, a [i].solve);

    return 0;
}