static void Main()
{
var h = Read();
var n = h[0];
var es = Array.ConvertAll(new bool[h[1]], _ => Read());
var mf = new MaxFlow(n);
mf.AddEdges(es);
Console.WriteLine(mf.Dinic(0, n - 1));
}
// このコードはテンプレートとして使えます。
// 0 <= v1 < n1, 0 <= v2 < n2
public static int[][] BipartiteMatching(int n1, int n2, int[][] des)
{
var sv = n1 + n2;
var ev = sv + 1;
var mf = new MaxFlow(ev + 1);
for (int i = 0; i < n1; ++i)
{
mf.AddEdge(sv, i, 1);
}
for (int j = 0; j < n2; ++j)
{
mf.AddEdge(n1 + j, ev, 1);
}
foreach (var e in des)
{
mf.AddEdge(e[0], n1 + e[1], 1);
}
mf.Dinic(sv, ev);
var map = mf.Map;
var r = new List <int[]>();
foreach (var se in map[sv])
{
if (se.Capacity > 0)
{
continue;
}
foreach (var e in map[se.To])
{
if (e.Capacity == 0)
{
r.Add(new[] { se.To, e.To - n1 });
break;
}
}
}
return(r.ToArray());
}
static object Solve()
{
var(h, w, n) = Read3();
var ps = Array.ConvertAll(new bool[n], _ => Read4());
var sv = 400;
var ev = sv + 1;
var mf = new MaxFlow(ev + 1);
for (int i = 0; i < h; i++)
{
mf.AddEdge(sv, i, 1);
}
for (int i = 0; i < w; i++)
{
mf.AddEdge(300 + i, ev, 1);
}
for (int i = 0; i < n; i++)
{
var(a, b, c, d) = ps[i];
var ri = 100 + i;
var ci = 200 + i;
mf.AddEdge(ri, ci, 1);
for (int j = a - 1; j < c; j++)
{
mf.AddEdge(j, ri, 1);
}
for (int j = b - 1; j < d; j++)
{
mf.AddEdge(ci, 300 + j, 1);
}
}
return(mf.Dinic(sv, ev));
}
static void Main()
{
var(n, m) = Read2();
var s = Array.ConvertAll(new bool[n], _ => Console.ReadLine().ToCharArray());
var sv = n * m;
var ev = sv + 1;
var mf = new MaxFlow(ev + 1);
var vs0 = new List <int>();
var vs1 = new HashSet <int>();
// checker board
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
{
if (s[i][j] == '#')
{
continue;
}
var v = m * i + j;
if ((i + j) % 2 == 0)
{
mf.AddEdge(sv, v, 1);
vs0.Add(v);
}
else
{
mf.AddEdge(v, ev, 1);
vs1.Add(v);
}
}
}
foreach (var v in vs0)
{
if (vs1.Contains(v - m))
{
mf.AddEdge(v, v - m, 1);
}
if (vs1.Contains(v + m))
{
mf.AddEdge(v, v + m, 1);
}
if (v % m != 0 && vs1.Contains(v - 1))
{
mf.AddEdge(v, v - 1, 1);
}
if (v % m != m - 1 && vs1.Contains(v + 1))
{
mf.AddEdge(v, v + 1, 1);
}
}
var M = mf.Dinic(sv, ev);
var map = mf.Map;
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
{
if (s[i][j] == '#')
{
continue;
}
var v = m * i + j;
if ((i + j) % 2 == 0)
{
var v2 = map[v].FirstOrDefault(e => e.Capacity == 0 && e.To != sv)?.To;
if (v2 == null)
{
continue;
}
var(i2, j2) = ((int)v2 / m, (int)v2 % m);
if (i == i2)
{
s[i][Math.Min(j, j2)] = '>';
s[i][Math.Max(j, j2)] = '<';
}
else
{
s[Math.Min(i, i2)][j] = 'v';
s[Math.Max(i, i2)][j] = '^';
}
}
}
}
Console.WriteLine(M);
foreach (var r in s)
{
Console.WriteLine(new string(r));
}
}