'use strict'

class Main {
  solve() {
    const nab = input.nextIntArr();
    const seq = input.nextIntArr();
    return _.sum(_.diffArray(seq).map(e => Math.min(e * nab[1],nab[2])));
  }
}

class Underscore {
  sum(arr) { return arr.reduce((a,b)=>a+b); }
  min(arr, func) { if (func == null) {func = (a,b) => a - b} return arr.reduce((a,b) => func(a,b) < 0 ? a : b); }
  max(arr, func) { if (func == null) {func = (a,b) => a - b} return arr.reduce((a,b) => func(a,b) > 0 ? a : b); }
  sort(arr, func) { if (func == null) {func = (a,b) => a - b} return arr.sort(func) }
  range(start, stop, step) {
	if (stop == null) { stop = start || 0; start = 0; }
	if (!step) { step = stop < start ? -1 : 1; }
	const length = Math.max(Math.ceil((stop - start) / step), 0);
	const range = Array(length);
	for (var idx = 0; idx < length; idx++, start += step) { range[idx] = start; }
	return range;
  }
  first (array, n) {
    if (array == null || array.length < 1) return n == null ? void 0 : [];
    if (n == null) return array[0];
    return this.initial(array, array.length - n);
  };
  initial (array, n) { return array.slice.call(array, 0, Math.max(0, array.length - (n == null ? 1 : n))); }
  tail(array, n) { return array.slice.call(array, n == null ? 1 : n); }
  last (array, n) { if (n == null) return array[array.length - 1]; return this.tail(array, Math.max(0, array.length - n)); }
  sumArray (arr) { return this.tail(arr.reduce(((a,b,i) => {a.push(b + a[i]); return a}), [0])); }
  diffArray (arr) { const s = []; for (let i = 1; i < arr.length; ++i) { s.push(arr[i] - arr[i-1]); } return s; }
  binarySearch (array, key, iteratee) {
	const itr = (obj) => (typeof obj === 'object') ? obj[iteratee] : obj;
	const value = itr(obj);
	let low = 0, high = array.length;
	while (low < high) {
	  let mid = Math.floor((low + high) / 2);
	  if (itr(array[mid]) < value) low = mid + 1; else high = mid;
	}
	return low;
  };
}
const _ = new Underscore();

class Input {
  constructor() {
	this.cursor = 0;
	this.inputAll();
  }

  inputAll() {
	this.data = (require("fs").readFileSync("/dev/stdin", "utf8")).split('\n');
	return this.data;
  }

  /* 1行 or 複数行文字列 */
  nextLine(n) {
	if (n) {
	  const ret = this.data.slice(this.cursor, this.cursor + n);
	  this.cursor += n;
	  return ret;
	}
	return this.data[this.cursor++];
  }
  /* 1整数 */
  nextInt() { return parseInt(this.nextLine()); } 
  /* 一行文字配列 */
  nextStrArr() { return this.nextLine().split(' '); } 
  /* 一行整数配列 */
  nextIntArr() { return this.nextStrArr().map((e) => parseInt(e)); }
  /* 一行浮動小数点配列 */
  nextFloatArr() { return this.nextStrArr().map((e) => parseFloat(e)); }
  /* 複数行整数配列 */
  nextIntLine(n) { return this.nextLine(n).map((e) => parseInt(e)) }
  /* 複数行浮動小数点配列 */
  nextFloatLine(n) { return this.nextLine(n).map((e) => parseFloat(e)) }
  /* 複数行文字列二次元配列 */
  nextStrRange(n) { return this.nextLine(n).map((line) => line.split(' ')); }
  /* 複数行整数二次元配列 */
  nextIntRange(n) {
	return this.nextLine(n).map((line) => line.split(' ').map((e) => parseInt(e)));
  }
  /* 複数行浮動小数点数二次元配列 */
  nextFloatRange(n) {
	return this.nextLine(n).map((line) => line.split(' ').map((e) => parseFloat(e)));
  }
} 
const input = new Input();

const Out = (output) => {
  let ret;
  if (output == null) return;
  if (output === true) { ret = 'Yes'; }
  else if (output === false) { ret = 'No'; }
  else { ret = output; }
  console.log(ret);
}

Out(new Main().solve());


Measured memory_bytes: 28320