Duel

Two duelists decided to choose as a venue for the fight dark alley. Along this avenue n grows trees and shrubs. The distance between adjacent objects is equal to one meter. Duel decided to conduct the following rules. A tree is chosen as a starting point. Then, two trees are the same distance from the source are marked as a place to shoot. Duelists begin to move from the starting point in opposite directions. When opponents reach the marked trees, they were unfolding, and start shooting at each other.

A scheme of arrangement of trees along the avenue. Required to determine the number of ways to choose a starting point and a place for shooting under the rules of the duel.

Input

In the input file contains a string of characters '0 'and '1' - scheme of the alley. Trees are denoted by '1', the bushes - a symbol of '0'. The string length does not exceed 100000 characters.

Output

Bring out the many ways to choose a starting point and a place for shooting under the rules of the duel.

Examples

Note

In the first example, the following configuration of the duel (the starting tree and trees to shoot in bold): 101010101, 101010101, 101010101 и 101010101.