import os; LOCAL = "INSIDE_EMACS" in os.environ
I = input; II, FL = lambda: int(I()), lambda: map(int, I().split()); FLL = lambda: [*FL()]
DEC, INC, YN = lambda x: x-1, lambda x: x+1, lambda y: print('YES' if y else 'NO')
R, E, S, P, L, F, RV, INF = range, enumerate, sorted, print, len, filter, reversed, float('inf')
def solve():
h = [[], []]
for _ in R(II()):
s = I().split()
h[s[1]=='R'] += int(s[0]),
P(sum(abs(lst[i] - lst[i-1]) for lst in h for i in R(1, len(lst))))
if LOCAL: [solve() for _ in R(II())]
else: solve()