Petya loves lucky numbers very much. Everybody knows that lucky numbers are positive integers whose decimal record contains only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.

Petya has an array $*a*$ of $*n*$ integers. The numbers in the array are numbered starting from $1$. Unfortunately, Petya has been misbehaving and so, his parents don't allow him play with arrays that have many lucky numbers. It is guaranteed that no more than $1000$ elements in the array $*a*$ are lucky numbers.

Petya needs to find the number of pairs of non-intersecting segments $[*l*_{1};*r*_{1}]$ and $[*l*_{2};*r*_{2}]$ ($1 ≤ *l*_{1} ≤ *r*_{1} < *l*_{2} ≤ *r*_{2} ≤ *n*$, all four numbers are integers) such that there's no such lucky number that occurs simultaneously in the subarray $*a*[*l*_{1}..*r*_{1}]$ and in the subarray $*a*[*l*_{2}..*r*_{2}]$. Help Petya count the number of such pairs.

Input

The first line contains an integer $*n*$ $(2 ≤ *n* ≤ 10^{5})$ — the size of the array $*a*$. The second line contains $*n*$ space-separated integers $*a*_{*i*}$ ($1 ≤ *a*_{*i*} ≤ 10^{9}$) — array $*a*$. It is guaranteed that no more than $1000$ elements in the array $*a*$ are lucky numbers.

Output

On the single line print the only number — the answer to the problem.

Please do not use the %lld specificator to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specificator.

Note

The subarray $*a*[*l*..*r*]$ is an array that consists of elements $*a*_{*l*}$, $*a*_{*l* + 1}$, ..., $*a*_{*r*}$.

In the first sample there are $9$ possible pairs that satisfy the condition: $[1, 1]$ and $[2, 2]$, $[1, 1]$ and $[2, 3]$, $[1, 1]$ and $[2, 4]$, $[1, 1]$ and $[3, 3]$, $[1, 1]$ and $[3, 4]$, $[1, 1]$ and $[4, 4]$, $[1, 2]$ and $[3, 3]$, $[2, 2]$ and $[3, 3]$, $[3, 3]$ and $[4, 4]$.

In the second sample there is only one pair of segments — $[1;1]$ and $[2;2]$ and it satisfies the condition.