#include <iostream>
#include <queue>
#include <cstdio>
#define REP(i,a,n) for(int i=a;i<=n;++i)
using namespace std;
typedef long long ll;const int N = 1e4+10;
int n, dep[N];
struct _ {int to,w;};
vector<_> g[N];
int dp[N][2];
ll ans;void dfs(int x, int fa, int d) {dep[x] = d, ++ans;ll c00 = 0, c11 = 0;for (_ e:g[x]) if (e.to!=fa) {int y = e.to;dfs(y,x,d+e.w&1);ans += 6ll*c00*dp[y][0];ans += 6ll*c11*dp[y][1];ans += 6*dp[y][dep[x]];ans += 12ll*dp[x][dep[x]]*dp[y][dep[x]];ans += 6ll*dp[y][dep[x]]*(dp[y][dep[x]]-1)/2;ans += 6ll*dp[x][!dep[x]]*dp[y][!dep[x]];c00 += (ll)dp[y][0]*dp[x][0];c11 += (ll)dp[y][1]*dp[x][1];dp[x][0] += dp[y][0];dp[x][1] += dp[y][1];}for (_ e:g[x]) if (e.to!=fa) {int y = e.to;ans += 6ll*dp[y][0]*(dp[y][0]-1)/2*(dp[x][0]-dp[y][0]);ans += 6ll*dp[y][1]*(dp[y][1]-1)/2*(dp[x][1]-dp[y][1]);}++dp[x][dep[x]];
}int main() {scanf("%d", &n);REP(i,2,n) {int u, v, w;scanf("%d%d%d", &u, &v, &w);g[u].push_back({v,w});g[v].push_back({u,w});}dfs(1,0,0);printf("%lld\n", ans);
}

#include <iostream>
#include <queue>
#include <cstdio>
#define REP(i,a,n) for(int i=a;i<=n;++i)
using namespace std;
typedef long long ll;const int N = 1e4+10;
int n, dep[N];
struct _ {int to,w;};
vector<_> g[N];
int dp[N][2], ans[2];void dfs(int x, int fa, int d) {++ans[d];for (_ e:g[x]) if (e.to!=fa) {int y = e.to;dfs(y,x,d+e.w&1);}
}int main() {scanf("%d", &n);REP(i,2,n) {int u, v, w;scanf("%d%d%d", &u, &v, &w);g[u].push_back({v,w});g[v].push_back({u,w});}dfs(1,0,0);printf("%lld\n",(ll)ans[0]*ans[0]*ans[0]+(ll)ans[1]*ans[1]*ans[1]);
}