View Compilation Error

67844_0_7365.cpp: In constructor `BigNum::BigNum(const char*)':
67844_0_7365.cpp:49: error: assignment of read-only location
67844_0_7365.cpp:52: error: assignment of read-only location
67844_0_7365.cpp:53: error: assignment of read-only location
67844_0_7365.cpp:54: error: assignment of read-only location
67844_0_7365.cpp:56: error: invalid conversion from `const void*' to `void*'
67844_0_7365.cpp:56: error:   initializing argument 1 of `void* memset(void*, int, size_t)'