a,b,c=map(int,input().split())
if (a-b == 0):
    print("S")
elif (a-c == 0):
    print("S")
elif (b-c == 0):
    print("S")
elif ((a+b)-c == 0):
    print("S")
elif((b+c)-a == 0):
    print("S")
elif((a+c)-b == 0):
    print("S")
else:
    print("N")
