add transpose of a directed graph
add transpose of a directed graph

shijiaxing/algorithms,switchkiller/algorithms,greyg00s/algorithms,hengwusanren/algorithms,noname007/algorithms,zhenglaizhang/algorithms,sigma-random/algorithms,fw1121/algorithms,ashwini0529/algorithms-1,qvex/algorithms,fengzhyuan/algorithms,xmfbit/algorithms,hengwusanren/algorithms,jacklicn/algorithms,NoSmartNoMan/algorithms,dumubuchenglin/algorithms,zhenglaizhang/algorithms,tempbottle/algorithms,xtaci/algorithms,lanbing510/Algorithms,shijiaxing/algorithms,tempbottle/algorithms,allengaller/algorithms,jacklicn/algorithms,noname007/algorithms,fengzhyuan/algorithms,greyg00s/algorithms,xmfbit/algorithms,lanbing510/Algorithms,qvex/algorithms,xtaci/algorithms,M4573R/algorithms-1,switchkiller/algorithms,fw1121/algorithms,ashwini0529/algorithms-1,dumubuchenglin/algorithms,M4573R/algorithms-1,NoSmartNoMan/algorithms,allengaller/algorithms,sigma-random/algorithms