# Optimal way to split a array

Consider a array $$a$$ with $$n$$ elements .the goal is to divide the array into segments ,which are continuous,formally from $$1$$ to $$i$$ ,then $$i+1$$ to $$j$$ and $$j+1$$ to $$k$$ and so on .Cost for making a new segment is $$x$$ and also if a segment has a element that occurs $$i,i>1$$ times then final cost increases by $$i$$ .Find the minimum possible cost.

My idea is that at first i would need a segment so for $$a[0]$$ i will make one and then i will proceed in array and add current element greedily and by greedily by adding $$a[i]$$ the cost may not increase if it never occurred in current segment or if it has occurred then i will check if cost increased by this element and cost for a new segment ,if cost is minimum in adding this element to current segment i will do this or else i will make a new segment starting with $$a[i]$$. But my greedy algorithm is wrong ,can anyone help me why my algorithm is worng?