diff --git a/src/LAB3.c b/src/LAB3.c
index df52d7d..b23b48a 100644
--- a/src/LAB3.c
+++ b/src/LAB3.c
@@ -44,7 +44,7 @@ double do_while_fn(Context* ctx)
         r += iter_fn(ctx->x, i);
         ++i;
     }
-    while (i <= ctx->i);
+    while (i <= ctx->n);
 
     return r;
 }
@@ -57,8 +57,20 @@ void lab_3()
         printf("Enter [x]: ");
         READ_EXACT("%lf", ctx.x);
 
-        printf("Enter [N]: ");
-        READ_EXACT("%u", ctx.n);
+        do
+        {
+            printf("Enter [N]: ");
+            READ_EXACT("%u", ctx.n);
+
+            if (ctx.n < ctx.i)
+            {
+                printf("N could not be less than I=1, try again\n");
+                continue;
+            }
+
+            break;
+        }
+        while(1);
 
         LoopFn* loop_fn;