func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long mod = 811287553;   long long powmod(long long a, long long b) {     long long res = 1;     a %= mod;     for (; b; b >>= 1) {       if (b & 1) res = res * a % mod;       a = a * a % mod;     }     return res;   }   int n, m, s, t, a, b, d;   vector<long long> dist, dist1;   vector<pair<int, int> > grh[2][100000];   vector<pair<pair<int, int>, int> > queries;   set<pair<int, int> > absEdges;   map<pair<int, int>, int> minEdges;   long long reachableCnt[2][100000];   const long long INF = 1000000000000;   void dijkstra(int src, vector<long long>& d, int mode) {     d.resize(n, INF);     d[src] = 0;     priority_queue<pair<long long, int> > pq;     pq.push(make_pair(0, src));     while (!pq.empty()) {       long long topD = -pq.top().first;       int topIdx = pq.top().second;       pq.pop();       if (d[topIdx] < topD) continue;       int sz = grh[mode][topIdx].size();       for (int i = 0; i < (int)sz; i++) {         int nIdx = grh[mode][topIdx][i].first;         int nD = grh[mode][topIdx][i].second;         long long nD1 = topD + nD;         if (d[nIdx] > nD1) {           d[nIdx] = nD1;           pq.push(make_pair(-nD1, nIdx));         }       }     }   }   int calReachable(int idx, vector<long long>& d, bool rev) {     if (rev && idx == s) {       reachableCnt[!rev][idx] = 1;       return 1;     }     if (!rev && idx == t) {       reachableCnt[!rev][idx] = 1;       return 1;     }     long long& ret = reachableCnt[!rev][idx];     if (ret != -1) return ret;     int ret1 = 0;     int sz = grh[rev][idx].size();     for (int i = 0; i < (int)sz; i++) {       int nIdx = grh[rev][idx][i].first;       int nD = grh[rev][idx][i].second;       if (d[nIdx] == d[idx] + nD) {         ret1 += calReachable(nIdx, d, rev);         ret1 %= mod;       }     }     return ret = (ret1 % mod);   }   int main() {     cin >> n >> m >> s >> t;     s--, t--;     for (int i = 0; i < (int)m; i++) {       cin >> a >> b >> d;       a--, b--;       grh[0][a].push_back(make_pair(b, d));       grh[1][b].push_back(make_pair(a, d));       queries.push_back(make_pair(make_pair(a, b), d));       if (minEdges.count(make_pair(a, b)))         minEdges[make_pair(a, b)] = min(minEdges[make_pair(a, b)], d);       else         minEdges[make_pair(a, b)] = d;     }     memset(reachableCnt, -1, sizeof(reachableCnt));     dijkstra(s, dist, 0);     dijkstra(t, dist1, 1);     calReachable(t, dist1, 1);     calReachable(s, dist, 0);     for (int i = 0; i < (int)m; i++) {       int x = queries[i].first.first, y = queries[i].first.second,           d = queries[i].second;       if ((((reachableCnt[0][x] * reachableCnt[1][y]) % mod) ==            reachableCnt[0][t]) &&           minEdges[make_pair(x, y)] < d) {         if (minEdges[make_pair(x, y)] == 1)           cout <<  NO  << endl;         else           cout <<  CAN   << d - minEdges[make_pair(x, y)] + 1 << endl;       } else {         long long d1 = dist[x] + dist1[y];         if ((((reachableCnt[0][x] * reachableCnt[1][y]) % mod) ==              reachableCnt[0][t])) {           if (d1 + d == dist[t])             cout <<  YES  << endl;           else {             if (d > 1 && d1 + 1 < dist[t])               cout <<  CAN   << d + d1 - (dist[t] - 1) << endl;             else               cout <<  NO  << endl;           }         } else {           if (d > 1 && d1 + 1 < dist[t])             cout <<  CAN   << d + d1 - (dist[t] - 1) << endl;           else             cout <<  NO  << endl;         }       }     }     return 0;   }   