uva 10038 - Jolly Jumpers

#include <iostream>
#include <cstdio>
#include <stdlib.h>
using namespace std;

int seq[3001], diff[3001];

int main()
{
int n, i, j, flag, min_index;
while(scanf("%d", &n) != EOF)
{
for (i = 1; i <= n; i++)    // initial
scanf("%d", &seq[i]);

for (i = 1; i <= n-1; i++)    // the difference
diff[i] = abs(seq[i+1] - seq[i]);

for(i = 1; i < n-1; i++)    // select_sort
{
min_index = i;
for (j = i+1; j <= n-1; j++)
{
if (diff[j] < diff[min_index])
{
min_index = j;
}
}
swap(diff[i], diff[min_index]);
}

flag = 1;
for (i = 1; i <= n-1; i++)
{
if (diff[i] != i)
{
cout << "Not jolly" << endl;
flag = 0;
break;
}
}
if(flag)
cout << "Jolly" << endl;
}

return 0;
}