added Kruskal's Algorithm in Greedy approach

greedy_approach/Kruskal's Algorithm.c

@@ -0,0 +1,111 @@
+#include <stdio.h>
+
+#define MAX 30
+
+typedef struct edge {
+    int u, v, w;
+} edge;
+
+typedef struct edge_list {
+    edge data[MAX];
+    int n;
+} edge_list;
+
+edge_list elist;
+
+int Graph[MAX][MAX], n;
+edge_list spanlist;
+
+void kruskalAlgo();
+int find(int belongs[], int vertexno);
+void applyUnion(int belongs[], int c1, int c2);
+void sort();
+void print();
+
+// Applying Kruskal Algo
+void kruskalAlgo() {
+    int belongs[MAX], i, j, cno1, cno2;
+    elist.n = 0;
+
+    for (i = 1; i < n; i++)
+        for (j = 0; j < i; j++) {
+            if (Graph[i][j] != 0) {
+                elist.data[elist.n].u = i;
+                elist.data[elist.n].v = j;
+                elist.data[elist.n].w = Graph[i][j];
+                elist.n++;
+            }
+        }
+
+    sort();
+
+    for (i = 0; i < n; i++)
+        belongs[i] = i;
+
+    spanlist.n = 0;
+
+    for (i = 0; i < elist.n; i++) {
+        cno1 = find(belongs, elist.data[i].u);
+        cno2 = find(belongs, elist.data[i].v);
+
+        if (cno1 != cno2) {
+            spanlist.data[spanlist.n] = elist.data[i];
+            spanlist.n = spanlist.n + 1;
+            applyUnion(belongs, cno1, cno2);
+        }
+    }
+}
+
+int find(int belongs[], int vertexno) {
+    return (belongs[vertexno]);
+}
+
+void applyUnion(int belongs[], int c1, int c2) {
+    int i;
+
+    for (i = 0; i < n; i++)
+        if (belongs[i] == c2)
+            belongs[i] = c1;
+}
+
+// Sorting algo
+void sort() {
+    int i, j;
+    edge temp;
+
+    for (i = 1; i < elist.n; i++)
+        for (j = 0; j < elist.n - 1; j++)
+            if (elist.data[j].w > elist.data[j + 1].w) {
+                temp = elist.data[j];
+                elist.data[j] = elist.data[j + 1];
+                elist.data[j + 1] = temp;
+            }
+}
+
+// Printing the result
+void print() {
+    int i, cost = 0;
+
+    for (i = 0; i < spanlist.n; i++) {
+        printf("\n%d - %d : %d", spanlist.data[i].u, spanlist.data[i].v, spanlist.data[i].w);
+        cost = cost + spanlist.data[i].w;
+    }
+
+    printf("\nSpanning tree cost: %d", cost);
+}
+
+int main() {
+    int i, j, total_cost;
+
+    printf("Enter the number of vertices: ");
+    scanf("%d", &n);
+
+    printf("Enter the adjacency matrix (0 for no edge, weight for edge):\n");
+    for (i = 0; i < n; i++)
+        for (j = 0; j < n; j++)
+            scanf("%d", &Graph[i][j]);
+
+    kruskalAlgo();
+    print();
+    return 0;
+}