How to find last digit of A^B
Step I : Find B mod 4* (or remainder by 4*) [say R=0**,1,2,3]
Step II : Write the last digit of base [say L]
Step III: Solve L^R
[**Note: If R=0, put R=4 instead of 0, or For Odd base direct answer is 1, and for even it's 6]
Step IV : The last digit of L^R is your required last digit.
e.g : Find the last digit of 1234567^55555555
Step I : 55555555 mod 4 = 3 [easy just check for last two digits]
Step II: 7
Step III : 7^3 =343
Step IV : Required Answer = 3
*Last digit is nothing but remainder by 10. The cyclicity of 10 is 4
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