# CSAW CTF Qualification Round 2019 : Count On Me
**category** : crypto
**points** : 100
**solves** : 120
## write-up
Find the seed that produce duplicated blocks
Because we have the first 16 characters, we can use the first block to solve the other block by xor
flag: `flag{U_c@n_coUn7_0n_m3_l1kE_123}`
# other write-ups and resources