add .gitignore

Signed-off-by: JIANG Di <dd19941105@gmail.com>
add 2012339930013蒋迪.pdf

Signed-off-by: JIANG Di <dd19941105@gmail.com>
Signed-off-by: JIANG Di <dd19941105@gmail.com>

	modified:   TopologicalSort.c
Signed-off-by: JIANG Di <dd19941105@gmail.com>

	modified:   TransitiveBinaryRelation.c
Signed-off-by: JIANG Di <dd19941105@gmail.com>

	modified:   TransitiveBinaryRelation01.c