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diff --git a/lib/util.ts b/lib/util.ts
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+++ b/lib/util.ts
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+/**
+ * Converts time in seconds to HH:mm format.
+ * @param time Time to convert in seconds.
+ */
+export function secondsToTimeString(time: number): string {
+  const h = Math.floor(time / 3600);
+  const m = Math.floor((time % 3600) / 60);
+
+  return `${h < 10 ? `0${h}` : h}:${m < 10 ? `0${m}` : m}`;
+}
+
+/**
+ * Calculates distance between two geographical points.
+ * @param latlng1 Coordinates of the first point.
+ * @param latlng2 Coordinates of the second point.
+ */
+export function distanceBetween(latlng1: number[], latlng2: number[]): number {
+  const R = 6371000;
+  const rad = Math.PI / 180;
+  const lat1 = latlng1[0] * rad;
+  const lat2 = latlng2[0] * rad;
+  const sinDLat = Math.sin(((latlng2[0] - latlng1[0]) * rad) / 2);
+  const sinDLon = Math.sin(((latlng2[1] - latlng1[1]) * rad) / 2);
+  const a = sinDLat * sinDLat + Math.cos(lat1) * Math.cos(lat2) * sinDLon * sinDLon;
+  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
+
+  return R * c;
+}
+
+export default { secondsToTimeString, distanceBetween };