#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <string>using namespace std;#define LL long long#define gc getchar()
inline int read() {int x = 0, f = 1; char c = gc;
while(c < '0' || c > '9') {if(c == '-') f = -1; c = gc;}
while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = gc; return x * f;}
inline LL read_LL() {LL x = 0; char c = gc; while(c < '0' || c > '9') c = gc;
while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = gc; return x;}
#undef gcconst int N = 1e5 + 10;int fa[N];
int A[N << 1], U[N << 1], V[N << 1], W[N << 1];
int n, m;bool Cmp(int a, int b) {return W[a] < W[b];}int Get(int x) {return fa[x] == x ? x : fa[x] = Get(fa[x]);}void Minst(int &R) {for(int i = 1; i <= n; i ++) fa[i] = i;int js = 0;for(int i = 1; i <= m; i ++) {int fu = Get(U[A[i]]), fv = Get(V[A[i]]);if(fu != fv) {fa[fu] = fv;js ++;}if(js == n - 1) {R = i;while(W[A[R + 1]] == W[A[i]]) R ++;return ;}}
}inline long long Maxst(int R) {for(int i = 1; i <= n; i ++) fa[i] = i;int js = 0;long long ret = 0;for(int i = R; i >= 1; i --) {int fu = Get(U[A[i]]), fv = Get(V[A[i]]);if(fu != fv) {fa[fu] = fv;ret += W[A[i]];js ++;}if(js == n - 1) return ret;}
}int main() {n = read(), m = read();for(int i = 1; i <= m; i ++) A[i] = i, U[i] = read(), V[i] = read(), W[i] = read();sort(A + 1, A + m + 1, Cmp);int R;Minst(R);cout << Maxst(R);return 0;
}

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <string>using namespace std;#define LL long long#define gc getchar()
inline int read() {int x = 0; char c = gc; while(c < '0' || c > '9') c = gc;
while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = gc; return x;}
inline LL read_LL() {LL x = 0; char c = gc; while(c < '0' || c > '9') c = gc;
while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = gc; return x;}
#undef gcconst int N = 410, oo = 999999999;int Map[N][N], Bmap[N][N];
int n, m;int main() {n = read(), m = read();for(int i = 1; i <= n; i ++) for(int j = 1; j <= n; j ++) Map[i][j] = oo;for(int i = 1; i <= n; i ++) Map[i][i] = 0;for(int i = 1; i <= n; i ++) for(int j = 1; j <= n; j ++) Bmap[i][j] = oo;for(int i = 1; i <= n; i ++) Bmap[i][i] = 0;for(int i = 1; i <= m; i ++) {int u = read(), v = read();Map[u][v] = Map[v][u] = 1;}if(Map[1][n] == 1) {for(int i = 1; i <= n; i ++) for(int j = 1; j <= n; j ++) {if(i == j) continue;if(Map[i][j] == oo) Bmap[i][j] = 1;}for(int k = 1; k <= n; k ++)for(int i = 1; i <= n; i ++)for(int j = 1; j <= n; j ++)Bmap[i][j] = min(Bmap[i][j], Bmap[i][k] + Bmap[k][j]);if(Bmap[1][n] == oo) cout << -1;else cout << Bmap[1][n];} else {for(int k = 1; k <= n; k ++)for(int i = 1; i <= n; i ++)for(int j = 1; j <= n; j ++)Map[i][j] = min(Map[i][j], Map[i][k] + Map[k][j]);if(Map[1][n] == oo) cout << -1;else cout << Map[1][n];}return 0;
}

if(n == m) cout << "FHTAGN!";
else cout << "NO";