Compilare: user.cpp: In function ‘char nextch()’: user.cpp:10:37: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, BUF_SIZE, 1, fin); ^ user.cpp: In function ‘int main()’: user.cpp:28:29: warning: ‘b’ may be used uninitialized in this function [-Wmaybe-uninitialized] int n, t, ans, i, j, a, b; ^ user.cpp:28:26: warning: ‘a’ may be used uninitialized in this function [-Wmaybe-uninitialized] int n, t, ans, i, j, a, b; ^