init

3I.py

@@ -0,0 +1,32 @@
+import sys
+
+input_data = sys.stdin.read().split()
+N = int(input_data[0])
+M = int(input_data[1])
+K = int(input_data[2])
+S = int(input_data[3]) - 1
+edges = []
+ptr = 4
+for _ in range(M):
+    u = int(input_data[ptr]) - 1
+    v = int(input_data[ptr+1]) - 1
+    w = int(input_data[ptr+2])
+    edges.append((u, v, w))
+    ptr += 3
+INF = 10**15
+dp = [INF] * N
+dp[S] = 0
+for _ in range(K):
+    next_dp = [INF] * N
+    for u, v, w in edges:
+        if dp[u] != INF:
+            if dp[u] + w < next_dp[v]:
+                next_dp[v] = dp[u] + w
+    dp = next_dp
+res = []
+for val in dp:
+    if val == INF:
+        res.append("-1")
+    else:
+        res.append(str(val))
+print("\n".join(res))