made graph_read() cleaner

1 files changed, 34 insertions, 17 deletions

diff --git a/src/graph.c b/src/graph.c
index 11d6861..0a15f40 100644
--- a/src/graph.c
+++ b/src/graph.c
@@ -59,30 +59,47 @@ Graph *graph_read(const char *filename) {
     FILE *file = fopen(filename, "r");
     if (!file)
         return NULL;
-
+    
     char line[1024];
-    fgets(line, 1024, file);
-
+    if (!fgets(line, sizeof(line), file)) {
+        fclose(file);
+        return NULL;
+    }
+    
     int n = atoi(line);
-    if (!n)
+    if (n <= 0) {
+        fclose(file);
         return NULL;
+    }
+    
     Graph *g = graph_new(n);
-
-    char c = line[0];
-    int i = 0, j = 0;
-    while (fgets(line, 1024, file)) {
-        while (c != '\n') {
-            if (c == '1') {
-                graph_add_edge(g, i, j);
-                j++;
-            } else if (c == '0') {
-                j++;
+    if (!g) {
+        fclose(file);
+        return NULL;
+    }
+    
+    for (int i = 0; i < n; i++) {
+        if (!fgets(line, sizeof(line), file)) {
+            fprintf(stderr, "Error: Could not read row %d\n", i);
+            fclose(file);
+            return g;
+        }
+        
+        int j = 0;
+        int col = 0;
+        while (col < n && line[j] != '\0' && line[j] != '\n') {
+            if (line[j] == '1') {
+                graph_add_edge(g, i, col);
+                col++;
+            } else if (line[j] == '0') {
+                col++;
             }
-            c++;
+            // skip any other characters
+            j++;
         }
-        i++;
     }
-
+    
+    fclose(file);
     return g;
 }