Code:
#include stdio.h
#include limits.h
#include iostream
using namespace std;
// Number of components in the graph
#define V 9
// A utility function to find the component with minimum distance value, from
// the set of components not yet included in shortest path tree
int minDistance(int dist[], bool sptSet[])
{
// Initialize min value
int min = INT_MAX, min_index;
for (int v = 0; v < V; v++)
if (sptSet[v] == false && dist[v] <= min)
min = dist[v], min_index = v;
return min_index;
}
// A utility function to print the constructed distance array
void printSolution(int dist[], int n)
{
cout << "Component\tDistance from other component\n";
for (int i = 0; i < V; i++)
printf("%d\t\t%d\n", i, dist[i]);
}
// Funtion that implements Dijkstra's single source shortest path algorithm
// for a graph represented using adjacency matrix representation
void optimizeLength(int graph[V][V], int src)
{
int dist[V]; // The output array. dist[i] will hold the shortest
// distance from src to i
bool sptSet[V]; // sptSet[i] will true if component i is included in shortest
// path tree or shortest distance from src to i is finalized
// Initialize all distances as INFINITE and stpSet[] as false
for (int i = 0; i < V; i++)
dist[i] = INT_MAX, sptSet[i] = false;
// Distance of source component from itself is always 0
dist[src] = 0;
// Find shortest path for all components
for (int count = 0; count < V - 1; count++)
{
// Pick the minimum distance component from the set of components not
// yet processed. u is always equal to src in first iteration.
int u = minDistance(dist, sptSet);
// Mark the picked component as processed
sptSet[u] = true;
// Update dist value of the adjacent components of the picked component.
for (int v = 0; v < V; v++)
// Update dist[v] only if is not in sptSet, there is an edge from
// u to v, and total weight of path from src to v through u is
// smaller than current value of dist[v]
if (!sptSet[v] && graph[u][v] && dist[u] != INT_MAX && dist[u]
+ graph[u][v] < dist[v])
dist[v] = dist[u] + graph[u][v];
}
// print the constructed distance array
printSolution(dist, V);
}
// driver program to test above function
int main()
{
/* Let us create the example graph discussed above */
int graph[V][V] =
{ { 0, 4, 0, 0, 0, 0, 0, 8, 0 }, { 4, 0, 8, 0, 0, 0, 0, 11, 0 }, {
0, 8, 0, 7, 0, 4, 0, 0, 2 },
{ 0, 0, 7, 0, 9, 14, 0, 0, 0 }, { 0, 0, 0, 9, 0, 10, 0, 0,
0 }, { 0, 0, 4, 0, 10, 0, 2, 0, 0 }, { 0, 0, 0, 14,
0, 2, 0, 1, 6 }, { 8, 11, 0, 0, 0, 0, 1, 0, 7 }, {
0, 0, 2, 0, 0, 0, 6, 7, 0 } };
cout << "Enter the starting component: ";
int s;
cin >> s;
optimizeLength(graph, s);
return 0;
}
Output:
Enter the starting component: 1
Component Distance from other component
0 4
1 0
2 8
3 15
4 22
5 12
6 12
7 11
8 10
Enter the starting component: 6
Component Distance from other component
0 9
1 12
2 6
3 13
4 12
5 2
6 0
7 1
8 6
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