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I got runtime error in this problem. I can't find the mistake.
Please help me. Thinks.

#include <iostream>
#include <vector>
using namespace std;

struct node
{
short num;
node *next;
};

struct color
{
short co;
node *now,*head,*last;
}c[51];

short in[50],w;

bool DFS(short a,short &dest ...