import numpy as np

count = 0

grid = []

with open('input.txt') as file:
    num_cols = len(file.readline().strip('\n'))
    file.seek(0)
    num_lines = 0
    for line in file:
        num_lines += 1
        for i in range(num_cols):
            grid.append(line[i])
    
grid = np.array(grid).reshape((num_lines, num_cols))

beams = set()

for row in grid:
    for i in range(len(row)):
        if row[i] == 'S':
            beams.add(i)
        elif row[i] == '^':
            if i in beams:
                count += 1
                beams.remove(i)
                if i - 1 not in beams:
                    beams.add(i - 1)
                if i + 1 not in beams:
                    beams.add(i + 1)

print(count)