C update

1 files changed, 20 insertions, 14 deletions

diff --git a/challenge-264/zapwai/c/ch-2.c b/challenge-264/zapwai/c/ch-2.c
index 86096faa72..f4ae6d9082 100644
--- a/challenge-264/zapwai/c/ch-2.c
+++ b/challenge-264/zapwai/c/ch-2.c
@@ -16,31 +16,37 @@ void proc(int source[], int indices[], int slen) {
 
   int current_length = 0;
   for (int i = 0; i < slen; i++) {
-    /* target[current_length] = ; */
-    
+    int *post = malloc((slen - indices[i] - 1) * sizeof(int));
     int *pre = malloc(current_length * sizeof(int));
     for (int j = 0; j < current_length; j++)
       pre[j] = target[j];
+    for (int j = 0; j < slen - indices[i] - 1; j++)
+      post[j] = target[indices[i] + j];
 
-    int *post = malloc((slen - indices[i]) * sizeof(int));
-    for (int j = 0; j < slen - indices[i]; j++)
-      post[j] = target[j];
-
-    /* Work in progress... */
+    int skip = 0;		/* 0, or 1 if replacement occurs */
+    int current_value = NIL;		/* gets replaced */
+    if (current_length > indices[i]) {
+      current_value = target[indices[i]];
+      skip = 1;
+    }
     
+    target[indices[i]] = source[i];
+    if (current_value != NIL)
+      target[indices[i] + 1] = current_value;
+    
+    if (current_length > indices[i]) {
+      for (int j = 0; j < slen - indices[i] - 1; j++)
+	target[indices[i] + j + skip] = post[j];
+    }
+
     free(pre);
     free(post);
     current_length++;
-    
-      /* chunk = splice @target, indices[i]; */
-      /* target[indices[i]] = source[i]; */
-      /* push @target, @chunk; */
-    }
+  }
   printf("Output: { ");
   for (int i = 0; i < slen; i++)
     printf("%d ", target[i]);
   printf("}\n");
-  
 }
 
 int main() {
@@ -55,4 +61,4 @@ int main() {
   int source3[] = {1};
   int indices3[] = {0};
   proc(source3, indices3, sizeof(source3) / sizeof(int));
-}
+}
\ No newline at end of file