func_code_string: #include <bits/stdc++.h>   using namespace std;   template <typename T, typename U>   inline void smin(T &a, U b) {     if (a > b) a = b;   }   template <typename T, typename U>   inline void smax(T &a, U b) {     if (a < b) a = b;   }   inline void gn(long long &first) {     int sg = 1;     char c;     while (((c = getchar()) <  0  || c >  9 ) && c !=  - )       ;     c ==  -  ? (sg = -1, first = 0) : (first = c -  0 );     while ((c = getchar()) >=  0  && c <=  9 ) first = first * 10 + c -  0 ;     first *= sg;   }   inline void gn(int &first) {     long long t;     gn(t);     first = t;   }   inline void gn(unsigned long long &first) {     long long t;     gn(t);     first = t;   }   inline void gn(double &first) {     double t;     scanf( %lf , &t);     first = t;   }   inline void gn(long double &first) {     double t;     scanf( %lf , &t);     first = t;   }   int power(int a, int b, int m, int ans = 1) {     for (; b; b >>= 1, a = 1LL * a * a % m)       if (b & 1) ans = 1LL * ans * a % m;     return ans;   }   int N, M, E, W;   int dis[101000];   queue<int> Q;   int pre[101000], edg[101000][3], cnt[101000], val[101000];   map<pair<int, int>, int> state, flag;   vector<int> adj[101000];   int len = 0x3f3f3f3f, tot;   void Dijk(int s) {     memset(dis, 0x3f, sizeof(dis));     Q.push(s);     dis[s] = 0;     cnt[s] = 0;     val[s] = W;     while (!Q.empty()) {       int u = Q.front();       Q.pop();       for (int i = 0; i < adj[u].size(); i++) {         int v = adj[u][i], k;         if (!state[pair<int, int>(u, v)])           k = val[u] + 1;         else           k = val[u] - 1;         if (dis[v] > dis[u] + 1) {           dis[v] = dis[u] + 1;           pre[v] = u;           val[v] = k;           Q.push(v);         } else if (dis[v] == dis[u] + 1 && val[v] > k) {           val[v] = k;           pre[v] = u;           Q.push(v);         }       }     }   }   int main() {     int u, v, w;     scanf( %d%d , &N, &M);     for (int i = 0; i < M; i++) {       scanf( %d%d%d , &u, &v, &w);       adj[u].push_back(v);       adj[v].push_back(u);       state[pair<int, int>(u, v)] = w;       state[pair<int, int>(v, u)] = w;       edg[i][0] = u;       edg[i][1] = v;       edg[i][2] = w;       W += w;     }     Dijk(1);     u = N;     while (u != 1) {       flag[pair<int, int>(u, pre[u])] = 1;       flag[pair<int, int>(pre[u], u)] = 1;       u = pre[u];     }     tot = 0;     for (int i = 0; i < M; i++) {       u = edg[i][0];       v = edg[i][1];       w = edg[i][2];       if (!flag[pair<int, int>(u, v)] && w == 1)         tot++;       else if (flag[pair<int, int>(u, v)] && w == 0)         tot++;     }     printf( %d n , tot);     for (int i = 0; i < M; i++) {       u = edg[i][0];       v = edg[i][1];       w = edg[i][2];       if (!flag[pair<int, int>(u, v)] && w == 1) {         printf( %d %d 0 n , u, v);       } else if (flag[pair<int, int>(u, v)] && w == 0) {         printf( %d %d 1 n , u, v);       }     }     return 0;   }   