edit README.md
1. edit README.md
2. new b025.cpp
edit int tot -> long long int tot
b025.cpp edit ok
del cout...
31 and 61 have problem
unsigned long long int can't used to sol the problem
Merge branch 'feature/f1' into develop
using f3
edit README.md
Merge branch 'release/v0.1.0' into develop