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58 lines
1.3 KiB
Python
58 lines
1.3 KiB
Python
from __future__ import print_function
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def printDist(dist, V):
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print("\nVertex Distance")
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for i in range(V):
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if dist[i] != float('inf') :
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print(i,"\t",int(dist[i]),end = "\t")
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else:
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print(i,"\t","INF",end="\t")
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print()
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def minDist(mdist, vset, V):
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minVal = float('inf')
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minInd = -1
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for i in range(V):
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if (not vset[i]) and mdist[i] < minVal :
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minInd = i
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minVal = mdist[i]
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return minInd
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def Dijkstra(graph, V, src):
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mdist=[float('inf') for i in range(V)]
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vset = [False for i in range(V)]
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mdist[src] = 0.0
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for i in range(V-1):
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u = minDist(mdist, vset, V)
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vset[u] = True
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for v in range(V):
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if (not vset[v]) and graph[u][v]!=float('inf') and mdist[u] + graph[u][v] < mdist[v]:
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mdist[v] = mdist[u] + graph[u][v]
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printDist(mdist, V)
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if __name__ == "__main__":
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V = int(input("Enter number of vertices: ").strip())
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E = int(input("Enter number of edges: ").strip())
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graph = [[float('inf') for i in range(V)] for j in range(V)]
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for i in range(V):
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graph[i][i] = 0.0
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for i in range(E):
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print("\nEdge ",i+1)
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src = int(input("Enter source:").strip())
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dst = int(input("Enter destination:").strip())
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weight = float(input("Enter weight:").strip())
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graph[src][dst] = weight
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gsrc = int(input("\nEnter shortest path source:").strip())
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Dijkstra(graph, V, gsrc)
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