import sys
S = input()


def change2list(S):
    leng = len(S)
    Slist = [0 for i in range(leng)]
    for i in range(len(Slist)):
        Slist[i] = S[i]
    return Slist
change2list

Slist = change2list(S)
for i in range(len(Slist)):
    sys.stdout.write(Slist[i].swapcase())
sys.stdout.write("\n")