n, m = map(int, input().split())

max_replace = {}

for _ in range(m):
    b, c = map(int, input().split())
    if c > b:
        if b in max_replace:
            if c > max_replace[b]:
                max_replace[b] = c
        else:
            max_replace[b] = c

visited = set()
final_values = {}
total_delta = 0

for b in max_replace.keys():
    if b not in visited:
        path = []
        current = b
        while current in max_replace and current not in visited:
            visited.add(current)
            path.append(current)
            current = max_replace[current]
        # Determine final value
        final = final_values.get(current, current)
        # Update final_values for all nodes in path
        for node in path:
            final_values[node] = final
            total_delta += final - node

initial_sum = n * (n + 1) // 2
print(initial_sum + total_delta)