#include #include #include #include #define N_node 2500 + 50 #define N_edge 10000 + 100 #define INF 2000000000 using namespace std; typedef struct { int from ,to ,next ,cost ,flow; }STAR; STAR E[N_edge]; int list[N_node] ,tot; int mer[N_edge] ,s_x[N_node]; void add(int a ,int b ,int c ,int d) { E[++tot].from = a; E[tot].to = b; E[tot].cost = c; E[tot].flow = d; E[tot].next = list[a]; list[a] = tot; } bool spfa(int s ,int t ,int n) { int mark[N_node] = {0}; for(int i = 0 ;i <= n ;i ++) s_x[i] = INF; queueq; q.push(s); mark[s] = 1 ,s_x[s] = 0; memset(mer ,255 ,sizeof(mer)); while(!q.empty()) { int xin ,tou; tou = q.front(); q.pop(); mark[tou] = 0; for(int k = list[tou] ;k ;k = E[k].next) { xin = E[k].to; if(s_x[xin] > s_x[tou] + E[k].cost && E[k].flow) { s_x[xin] = s_x[tou] + E[k].cost; mer[xin] = k; if(!mark[xin]) { mark[xin] = 1; q.push(xin); } } } } return mer[t] != -1; } int M_C_Flow(int s ,int t ,int n ,int k) { if(!k) return 0; int minflow ,sum_peo = k ,now_peo = 0 ,list_time = 0 ,ans = INF; while(spfa(s ,t ,n)) { minflow = INF; for(int i = mer[t] ;i + 1 ;i = mer[E[i].from]) if(minflow > E[i].flow) minflow = E[i].flow; for(int i = mer[t] ;i + 1 ;i = mer[E[i].from]) E[i].flow -= minflow ,E[i^1].flow += minflow; sum_peo -= (s_x[t] - list_time) * now_peo + minflow; list_time = s_x[t] ,now_peo += minflow; int now = s_x[t] + (int)ceil((1.0 * (sum_peo < 0 ? 0 : sum_ ))/now_peo); if(ans > now) ans = now; if(sum_peo < 1) break; } return ans; } int main () { int n ,m ,k ,i ,a ,b ,c; while(~scanf("%d %d %d" ,&n ,&m ,&k)) { memset(list ,0 ,sizeof(list)); tot = 1; for(i = 1 ;i <= m ;i ++) { scanf("%d %d %d" ,&a ,&b ,&c); a ++ ,b ++; add(a ,b ,1 ,c) ,add(b ,a ,-1 ,0); } int ans = M_C_Flow(1 ,n ,n ,k); ans == INF ? puts("No solution"):printf("%d\n" ,ans); } return 0; }