import std.stdio, std.string, std.array, std.conv, std.algorithm, std.typecons, std.range, std.container, std.math, std.algorithm.searching, std.functional,std.mathspecial;

void main(){
    auto NAB=readln.split.map!(to!int).array;
    auto Xs=readln.split.map!(to!int).array;
    auto res=0L;
    foreach(i;0..NAB[0]-1){
        res+=min(NAB[1]*(Xs[i+1]-Xs[i]),NAB[2]);
    }
    writeln(res);
}
