t = input()

n = int(t.split(" ")[0]) # num of lines
m = int(t.split(" ")[1]) # length of lines

all = []

for x in range(n):
    all.append([*input()])


types = []
type_counter = []


for x in range(n):

    temp_type_counter = type_counter.copy()

    for y in range(len(types)):

        if all[x].copy().sort() != types[y].copy().sort(): continue
        else:
            
            #temp = all[x].copy()

            for z in range(m):
                if all[x] == types[y][z]:
                    type_counter[y] = type_counter[y] + 1
                    break
                """
                if temp == types[y]:
                    type_counter[y] = type_counter[y] + 1
                    break
                temp.append(temp[0])
                temp.pop(0)
                """
            
    if temp_type_counter == type_counter:
        temp = all[x].copy
        temp_2d = []
        for p in range(m):
            temp_2d.append(temp.copy())
            temp.append(temp[0])
            temp.pop(0)
        types.append(temp_2d.copy())
        type_counter.append(1)
        """
        types.append(all[x])
        type_counter.append(1)
        """


answer = 0

for l in range(len(type_counter)):
    answer = answer + ((type_counter[l]*(type_counter[l]-1))/2)

print(int(answer))