There live square people in a square country. Everything in this country is square also. Thus, the Square Parliament has passed a law about a land. According to the law each citizen of the country has a right to buy land. A land is sold in squares, surely. Moreover, a length of a square side must be a positive integer amount of meters. Buying a square of land with a side *a* one pays *a*^{2} quadrics (a local currency) and gets a square certificate of a landowner.

One citizen of the country has decided to invest all of his *N* quadrics into the land. He can, surely, do it, buying square pieces 1 × 1 meters. At the same time the citizen has requested to minimize an amount of pieces he buys: "It will be easier for me to pay taxes," — he has said. He has bought the land successfully.

Your task is to find out a number of certificates he has gotten.

### Input

The only line contains a positive integer *N* ≤ 60 000 , that is a number of quadrics that the citizen has invested.

### Output

The only line contains a number of certificates that he has gotten.

### Sample

**Problem Author: **Stanislav Vasilyev

**Problem Source: **Ural State Univerisity Personal Contest Online February'2001 Students Session