http://codepro.lge.com/apply/exam/ZXhfaUhjUkhfMTQ5NTQ5NjY4ODY3NQ==/quiz/cV9oUmVJa18xNTQ5ODUxNTIxMDEy
Source
const int FindMaxH(const int N, const int (&P)[MAX_N])
{
int h = 0;
int ud = 1;
for (int i=0; i<N; i++){
if(ud == 1){
if(P[i] > P[i+1]){
// go down
h += P[i];
ud = -1;
}
}
else{
if(P[i] < P[i+1]){
// go up
h -= P[i];
ud = 1;
}
}
}
return h;
}