UVa 11742 - Social Constraints

// aarifshuvo   ``CSEJU

#include <bits/stdc++.h>
#define ll long long
#define SZ(x) ((int)(x).size())
#define scl(x) scanf("%lld", &x)
#define scll(x,y) scanf("%lld %lld", &x, &y)
#define ALL(x) (x).begin(),(x).end()
#define REP(i,n) for(int i=0;i<n;i++)
#define REV(i,n) for(int i=n-1;i>=0;i--)
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define pri(a) cout<<a<<endl
#define prii(a,b) cout<<a<<" "<<b<<endl
using namespace std;

int main()
{
    ll n,m;
    ll arr[10],a[22],b[22],c[22];

    while(scll(n,m)==2 && n+m)
    {
        REP(i,m) scll(a[i],b[i]), scl(c[i]);

        REP(i,n) arr[i]=i;

        ll ans = 0,fl=1;

        do
        {
            REP(i,m)
            {
                ll df = abs(arr[a[i]]-arr[b[i]]);

                if(c[i]>0 and df<=c[i]) fl=1;
                else if(c[i]<0 and df>=(-c[i])) fl=1;
                else
                {
                    fl=0;
                    break;
                }
            }
            if(fl) ans++;
        }while(next_permutation(arr,arr+n));

        printf("%lld\n", ans);
    }
    return 0;
}