#include using namespace std; #define FOR(i,a,b) for(int i=(a);i<(b);++i) #define REP(i,n) FOR(i,0,n) #define ALL(v) begin(v),end(v) template inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; } using ll = long long; using pii = pair; constexpr ll INF = 1ll<<30; constexpr ll longINF = 1ll<<60; constexpr ll MOD = 1000000007; constexpr bool debug = false; //---------------------------------// int main() { int N, M; cin >> N >> M; vector S(M), T(M); vector D(M); REP(i, M) scanf("%d %d %lld", &S[i], &T[i], &D[i]), --S[i], --T[i]; REP(i, N) { vector dist(N, longINF); dist[i] = 0; REP(j, N + 1) REP(k, M) if (dist[S[k]] != longINF && chmin(dist[T[k]], dist[S[k]] + D[k]) && j == N) assert(false); ll ans = 0; REP(j, N) ans += dist[j] == longINF ? 0 : dist[j]; cout << ans << endl; } }