void main() {
    long[] tmp = readln.split.to!(long[]);
    long n = tmp[0], a = tmp[1], b = tmp[2];
    long[] x = readln.split.to!(long[]);
    long result;
    foreach (i; 1 .. n) {
        long diff = x[i] - x[i-1];
        result += min(a*diff, b);
    }
    result.writeln;
}

import std.stdio;
import std.string;
import std.array;
import std.conv;
import std.algorithm;
import std.range;
import std.math;
import std.numeric;
import std.container;
import std.typecons;
import std.ascii;
import std.uni;