# 668. Kth Smallest Number in Multiplication Table

Nearly every one have used the Multiplication Table. But could you find out the `k-th` smallest number quickly from the multiplication table?

Given the height `m` and the length `n` of a `m * n` Multiplication Table, and a positive integer `k`, you need to return the `k-th` smallest number in this table.

Example 1:

```Input: m = 3, n = 3, k = 5
Output:
Explanation:
The Multiplication Table:
1	2	3
2	4	6
3	6	9

The 5-th smallest number is 3 (1, 2, 2, 3, 3).
```

Example 2:

```Input: m = 2, n = 3, k = 6
Output:
Explanation:
The Multiplication Table:
1	2	3
2	4	6

The 6-th smallest number is 6 (1, 2, 2, 3, 4, 6).
```

Note:

1. The `m` and `n` will be in the range [1, 30000].
2. The `k` will be in the range [1, m * n]

awice’s solution

```def findKthNumber(self, m, n, k):
def enough(x):
return sum(min(x / i, n) for i in xrange(1, m+1)) >= k

lo, hi = 1, m*n
while lo < hi:
mi = (lo + hi) / 2
if not enough(mi):
lo = mi + 1
else:
hi = mi
return lo```

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