Initial commit

EulerCycle.c

@@ -0,0 +1,83 @@
+#include <stdio.h>
+#include <stdlib.h>
+#define MAX 2000
+
+int main(){
+    int ** graph, sequence[MAX];
+    int i,j,k,n,deg,eulCheck;
+    FILE *InputGraph;
+
+    /*Allocating enough memory for the 2D array so the program doesnt seg fault*/
+    graph = (int **)malloc(sizeof(int*)*MAX);
+    for(i = 0; i < MAX; i++){
+        graph[i] = (int*)malloc(sizeof(int)*MAX);
+    }
+    
+    /*Reads from the roper text file*/
+    InputGraph = fopen("euler-graphs.txt","r");
+
+    /*Loops through all 5 graphs */
+    for(k = 1; k <=5 ; k++){
+        eulCheck = 0;
+
+        /*Resets degree sequence */
+        for(i = 0; i < MAX; i++){ 
+            sequence[i] = 0;
+        }
+
+        /*Scans latest grpah size*/
+        fscanf(InputGraph, "%d", &n);
+
+        /*Finds the degree of every vertex and adds it to the sequence array*/
+        for(i = 0; i < n; i++){
+            deg = 0;
+            for(j = 0; j < n; j++){
+                fscanf(InputGraph, "%d", &graph[i][j]);
+                if(graph[i][j] == 1){
+                    deg++;
+                }
+            }
+
+            sequence[deg]++;
+
+        }
+        
+        /*Goes throught the latest degree sequence and deteremines if all
+        vertex degrees are even*/
+        for(i = 0; i < n; i++){
+            for(j = 0; j < sequence[i]; j++){
+                if((i%2) == 0){
+                    eulCheck++;
+                }
+            }
+        }
+
+        /*If all vertices are of an even degree then the program states 
+        that the given graph is Eulerian*/
+        if(eulCheck == n){
+            printf("Graph %d: Eulerian. \n", k);
+        } else {
+            printf("Graph %d: NOT Eulerian. \n", k);
+        }
+
+    } 
+
+    /*Frees allocated memory */
+    for(i = 0; i < MAX; i++){
+        free(graph[i]);
+    }
+    free(graph);
+    
+    fclose(InputGraph);
+
+    return 0;
+}
+
+/*
+What the program prints out:
+Graph 1: Eulerian. 
+Graph 2: NOT Eulerian. 
+Graph 3: NOT Eulerian. 
+Graph 4: Eulerian. 
+Graph 5: Eulerian. 
+*/