#D8219. Blackout
Blackout
Blackout
We have a grid with N rows and N columns. The cell at the i-th row and j-th column is denoted (i, j).
Initially, M of the cells are painted black, and all other cells are white. Specifically, the cells (a_1, b_1), (a_2, b_2), ..., (a_M, b_M) are painted black.
Snuke will try to paint as many white cells black as possible, according to the following rule:
- If two cells (x, y) and (y, z) are both black and a cell (z, x) is white for integers 1≤x,y,z≤N, paint the cell (z, x) black.
Find the number of black cells when no more white cells can be painted black.
Constraints
- 1≤N≤10^5
- 1≤M≤10^5
- 1≤a_i,b_i≤N
- All pairs (a_i, b_i) are distinct.
Input
The input is given from Standard Input in the following format:
N M a_1 b_1 a_2 b_2 : a_M b_M
Output
Print the number of black cells when no more white cells can be painted black.
Examples
Input
3 2 1 2 2 3
Output
3
Input
2 2 1 1 1 2
Output
4
Input
4 3 1 2 1 3 4 4
Output
3
inputFormat
Input
The input is given from Standard Input in the following format:
N M a_1 b_1 a_2 b_2 : a_M b_M
outputFormat
Output
Print the number of black cells when no more white cells can be painted black.
Examples
Input
3 2 1 2 2 3
Output
3
Input
2 2 1 1 1 2
Output
4
Input
4 3 1 2 1 3 4 4
Output
3
样例
2 2
1 1
1 2
4