From 682bb557af31dd905d13d5f36ab88b1373a5dd6f Mon Sep 17 00:00:00 2001
From: bronku <bronk.jakub@proton.me>
Date: Sun, 12 Oct 2025 23:00:27 +0200
Subject: [PATCH] record type

---
 TODO.md  | 14 ++++++++++++++
 record.h | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+)
 create mode 100644 TODO.md
 create mode 100644 record.h

diff --git a/TODO.md b/TODO.md
new file mode 100644
index 0000000..3e4112b
--- /dev/null
+++ b/TODO.md
@@ -0,0 +1,14 @@
+- [ ] file operations
+  - [ ] write to file (at index)
+  - [ ] read from file (at index)
+  - [ ] print_file (maybe just calling cat???)
+- [ ] a tape type - representing a file?
+- [x] a record type - x1,x2,x3,x4,x5
+  - [x] comparing records
+- [ ] natural merge sort
+- [ ] configuration
+  - [ ] cmd args - man getopts
+- [ ] file input
+- [ ] keyboard input
+- [ ] testing
+- [ ] report
diff --git a/record.h b/record.h
new file mode 100644
index 0000000..1eec490
--- /dev/null
+++ b/record.h
@@ -0,0 +1,39 @@
+#pragma once
+#include <stdio.h>
+
+typedef struct {
+    int a[5];
+    int x;
+} record;
+
+static inline int read_record(FILE* stream, record* out)
+{
+    int result = fscanf(stream, "%d %d %d %d %d %d", &out->a[0], &out->a[1], &out->a[2], &out->a[3], &out->a[4], &out->x);
+    if (result == 6) {
+        return 0;
+    }
+    if (result == EOF) {
+        return EOF;
+    }
+    return -2;
+}
+
+static inline int g(const record* x)
+{
+    int out = 0;
+    int x_n = 1;
+    for (int i = 0; i < 5; i++) {
+        out += x->a[i] * x_n;
+        x_n *= x->x;
+    }
+    return out;
+}
+
+static inline int compare_records(const void* a, const void* b)
+{
+    const record* ra = (const record*)a;
+    const record* rb = (const record*)b;
+    const int ga = g(ra);
+    const int gb = g(rb);
+    return (ga > gb) - (ga < gb);
+}