diff --git a/day07/input b/day07/input
new file mode 100644
index 0000000..06106e4
--- /dev/null
+++ b/day07/input
@@ -0,0 +1,1014 @@
+$ cd /
+$ ls
+dir dcvzbqf
+23804 gsdpmrq.bsz
+24936 nfngbl.mcn
+178747 plw.frm
+dir qdtw
+dir qmfvph
+$ cd dcvzbqf
+$ ls
+dir gfvl
+$ cd gfvl
+$ ls
+104564 dnbmm.bgc
+$ cd ..
+$ cd ..
+$ cd qdtw
+$ ls
+dir fsj
+dir jwfbvmds
+216592 pcg.wnr
+dir pwnhpm
+dir qbrpq
+dir wdc
+dir wpw
+dir zbfgmw
+$ cd fsj
+$ ls
+118575 ltbr.mdf
+$ cd ..
+$ cd jwfbvmds
+$ ls
+dir bbvg
+dir bds
+dir clvljpb
+44460 gwbbbgj.hbs
+dir hzqlb
+dir jpvnzhf
+61025 trdm.qps
+$ cd bbvg
+$ ls
+219031 zbzgvsb
+94339 zhfmsb.lvv
+$ cd ..
+$ cd bds
+$ ls
+133483 hzqlb
+$ cd ..
+$ cd clvljpb
+$ ls
+103511 bmm.dwc
+121211 clvljpb.fzn
+158145 dnbmm.fmm
+74998 pcg.wnr
+dir psvtz
+$ cd psvtz
+$ ls
+dir gdj
+167697 pcgjgc.wgl
+2613 qchfgv
+91712 qsdzj.jng
+$ cd gdj
+$ ls
+133897 qchfgv
+dir vmcshh
+93805 zgmvb.jfg
+$ cd vmcshh
+$ ls
+200517 zgwwvb.pcs
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd hzqlb
+$ ls
+dir dnbmm
+$ cd dnbmm
+$ ls
+223576 msrbz.wjs
+$ cd ..
+$ cd ..
+$ cd jpvnzhf
+$ ls
+20581 nfngbl.mcn
+$ cd ..
+$ cd ..
+$ cd pwnhpm
+$ ls
+dir clvljpb
+33727 hzqlb.zpp
+39037 lfjjf.pjt
+163662 mbwfhq.cjj
+236292 nfngbl.mcn
+189576 zvbgnbvf
+$ cd clvljpb
+$ ls
+dir clvljpb
+212906 clvljpb.pls
+214564 dnm
+dir fvgbsft
+230034 hzqlb.jvz
+48101 plw.frm
+237902 qchfgv
+$ cd clvljpb
+$ ls
+dir hzqlb
+dir zhq
+$ cd hzqlb
+$ ls
+189238 cvgp
+dir gjg
+$ cd gjg
+$ ls
+167082 ttltfz.bvz
+$ cd ..
+$ cd ..
+$ cd zhq
+$ ls
+203202 nfngbl.mcn
+212148 qhnnr.dhs
+$ cd ..
+$ cd ..
+$ cd fvgbsft
+$ ls
+dir fzhwsjf
+18477 nps
+dir vlplrn
+dir vnbg
+dir vpc
+$ cd fzhwsjf
+$ ls
+91220 clvljpb.png
+235721 pcg.wnr
+61559 qchfgv
+70762 vpr.nlc
+$ cd ..
+$ cd vlplrn
+$ ls
+260247 qrtnfmln.tpv
+$ cd ..
+$ cd vnbg
+$ ls
+43069 ttltfz.mzr
+dir wfb
+58219 zgwwvb.pcs
+272132 zhq.mrw
+$ cd wfb
+$ ls
+107068 clvljpb.mtp
+$ cd ..
+$ cd ..
+$ cd vpc
+$ ls
+185602 dnbmm.hfm
+100399 hzqlb.vtn
+259486 pcg.wnr
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd qbrpq
+$ ls
+138169 cntvzqfm.hgp
+216598 dnbmm.lhs
+116696 nfngbl.mcn
+35315 phf.rvn
+$ cd ..
+$ cd wdc
+$ ls
+270492 ghdzdq.ghg
+137119 lnt.nsd
+$ cd ..
+$ cd wpw
+$ ls
+dir dnbmm
+156266 jgfv.cpp
+156947 lvlqcrrs.djl
+dir lvznwbpg
+12199 nfngbl.mcn
+54105 nlsp
+86737 zhq.wmz
+$ cd dnbmm
+$ ls
+138125 lth.hcq
+80844 nhh.gzc
+149596 ttltfz.ntn
+$ cd ..
+$ cd lvznwbpg
+$ ls
+99156 ldtst.dcr
+217350 pcg.wnr
+247238 plw.frm
+dir qbqpsccr
+dir wnms
+dir zhq
+165426 zmhnzdmb.jnc
+$ cd qbqpsccr
+$ ls
+272199 pcg.wnr
+219600 wpjqjm.qwr
+257473 zhq.zmq
+$ cd ..
+$ cd wnms
+$ ls
+dir ttltfz
+$ cd ttltfz
+$ ls
+dir btm
+$ cd btm
+$ ls
+dir hzqlb
+$ cd hzqlb
+$ ls
+dir ttltfz
+$ cd ttltfz
+$ ls
+204980 hzqlb.hhm
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd zhq
+$ ls
+154868 srdfz
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd zbfgmw
+$ ls
+dir fcjwpgz
+dir ttltfz
+dir zhq
+$ cd fcjwpgz
+$ ls
+dir jltvg
+9958 qchfgv
+dir wwqrb
+$ cd jltvg
+$ ls
+6370 bssvrjdq.mnr
+$ cd ..
+$ cd wwqrb
+$ ls
+157805 npdl
+237057 qchfgv
+dir twrp
+259572 vptsgw
+176388 zgwwvb.pcs
+91956 zhq
+$ cd twrp
+$ ls
+dir sfvntjwf
+$ cd sfvntjwf
+$ ls
+68331 hdwfg.jrl
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ttltfz
+$ ls
+41183 plw.frm
+$ cd ..
+$ cd zhq
+$ ls
+32950 dmzbmrdr.gtq
+dir zhq
+$ cd zhq
+$ ls
+195502 dmgmwbf
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd qmfvph
+$ ls
+dir cwfh
+dir dnbmm
+dir mmmdpth
+4841 pcg.wnr
+dir prnpbn
+111478 sgmg.hbs
+dir ttltfz
+178296 ttltfz.mjc
+dir zcvfqn
+dir zhq
+32446 zhq.pjm
+dir zpb
+$ cd cwfh
+$ ls
+dir dswtm
+dir mwzjf
+$ cd dswtm
+$ ls
+70390 fmq.mrp
+108185 qjlfnlp
+189923 zhq.njc
+$ cd ..
+$ cd mwzjf
+$ ls
+122536 glmpd.mdl
+108226 nfngbl.mcn
+dir qbvffr
+33192 ttltfz
+195824 zgwwvb.pcs
+$ cd qbvffr
+$ ls
+147595 pcg.wnr
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd dnbmm
+$ ls
+dir cbdl
+dir fhqjzf
+56752 gsgrnf.mlt
+dir ndp
+67967 nfngbl.mcn
+dir swgwdv
+$ cd cbdl
+$ ls
+263964 dnrbtr.lbh
+66120 qchfgv
+dir qwvd
+$ cd qwvd
+$ ls
+dir dnbmm
+143315 mhlswpcd.lpt
+199969 ncdrrp.ljf
+$ cd dnbmm
+$ ls
+122474 pcg.wnr
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd fhqjzf
+$ ls
+dir fnnbrlc
+dir hzqlb
+254128 pcg.wnr
+168008 plw.frm
+dir vwgvd
+dir zhq
+$ cd fnnbrlc
+$ ls
+156413 dnbmm.ngb
+30790 zbfnjnnz.csg
+$ cd ..
+$ cd hzqlb
+$ ls
+267451 cgzrdpr
+77460 nfngbl.mcn
+205978 plw.frm
+66224 sjw.ctb
+212873 zgwwvb.pcs
+$ cd ..
+$ cd vwgvd
+$ ls
+161177 phdbz.tmc
+$ cd ..
+$ cd zhq
+$ ls
+dir hchlgv
+218946 rfngrlz.zzr
+dir zhq
+$ cd hchlgv
+$ ls
+dir dnbmm
+270943 hcpnwbd
+dir hzqlb
+13433 wdljw.cgn
+$ cd dnbmm
+$ ls
+150415 pcg.wnr
+$ cd ..
+$ cd hzqlb
+$ ls
+44475 qcvwtfg.wrl
+$ cd ..
+$ cd ..
+$ cd zhq
+$ ls
+155076 ggndpjzp.rpz
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ndp
+$ ls
+112146 nfw.htp
+207815 vqwtw.qff
+$ cd ..
+$ cd swgwdv
+$ ls
+dir dmqn
+dir fzgdjp
+205897 hzqlb.vtm
+226944 nfngbl.mcn
+259443 nrfpz.vmn
+136591 zgwwvb.pcs
+$ cd dmqn
+$ ls
+258693 gdplrzt.wzf
+141489 hzqlb
+225488 pghz.brw
+$ cd ..
+$ cd fzgdjp
+$ ls
+206026 msthjppp
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd mmmdpth
+$ ls
+dir clvljpb
+dir hzqlb
+263747 pcg.wnr
+$ cd clvljpb
+$ ls
+168342 qhgndmj
+$ cd ..
+$ cd hzqlb
+$ ls
+dir lqvgqhw
+$ cd lqvgqhw
+$ ls
+218324 swnjhbj.cqt
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd prnpbn
+$ ls
+dir dndnhn
+176959 gzhtvt
+85765 hzqlb.clg
+120691 nfngbl.mcn
+245942 qchfgv
+43951 zgwwvb.pcs
+$ cd dndnhn
+$ ls
+235760 dhvvnqpt
+dir hvg
+dir jqvmzg
+dir mhz
+$ cd hvg
+$ ls
+167698 zqbj
+$ cd ..
+$ cd jqvmzg
+$ ls
+218904 wppv.mqz
+dir zlp
+$ cd zlp
+$ ls
+8030 wvj.gld
+$ cd ..
+$ cd ..
+$ cd mhz
+$ ls
+37541 tdfvwqlj
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ttltfz
+$ ls
+dir dnbmm
+dir ttltfz
+dir wbvcf
+dir wsqvpp
+148645 zgwwvb.pcs
+$ cd dnbmm
+$ ls
+116852 mjzgll.bcp
+$ cd ..
+$ cd ttltfz
+$ ls
+dir hzqlb
+dir msczpj
+dir mvbhn
+38087 nfngbl.mcn
+dir ttjbnj
+dir ttltfz
+dir vjj
+dir zhq
+dir zqgcbnrt
+$ cd hzqlb
+$ ls
+dir jshj
+dir jtjv
+dir mgfwthq
+dir zhq
+$ cd jshj
+$ ls
+235605 cldpdjp.cbc
+dir clvljpb
+dir dzcnm
+dir hmvw
+dir hzqlb
+dir ltpqhg
+12951 qchfgv
+dir wzvjft
+$ cd clvljpb
+$ ls
+65802 lnpjlj
+25402 qrtrvmwl.fms
+$ cd ..
+$ cd dzcnm
+$ ls
+dir cpnwcv
+dir hzqlb
+dir mjclcntf
+dir qnljb
+237105 rlpvq.fbf
+dir zhq
+$ cd cpnwcv
+$ ls
+27600 qbgclqc.tdd
+$ cd ..
+$ cd hzqlb
+$ ls
+168016 zhq
+$ cd ..
+$ cd mjclcntf
+$ ls
+dir clvljpb
+dir qpjtr
+43145 zgwwvb.pcs
+$ cd clvljpb
+$ ls
+15025 plw.frm
+$ cd ..
+$ cd qpjtr
+$ ls
+54909 zhq
+$ cd ..
+$ cd ..
+$ cd qnljb
+$ ls
+49366 clvljpb.vtg
+52193 fnd.tfr
+$ cd ..
+$ cd zhq
+$ ls
+105765 dfnqhggg.cfj
+dir hfzgs
+135556 spff
+129957 vzgjrc.cbs
+$ cd hfzgs
+$ ls
+52456 ttltfz.fdq
+31345 wcmf.hsd
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd hmvw
+$ ls
+77175 flhlwq.rqc
+dir gmvqz
+252279 gnmvm
+dir lmbqfhb
+$ cd gmvqz
+$ ls
+129431 dnbmm.lwl
+$ cd ..
+$ cd lmbqfhb
+$ ls
+dir wjql
+$ cd wjql
+$ ls
+48687 cgtbqqq.zzs
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd hzqlb
+$ ls
+105333 mqsgqph
+dir zhq
+$ cd zhq
+$ ls
+116802 hbtlhjn.dvs
+8842 pcg.wnr
+211096 plw.frm
+$ cd ..
+$ cd ..
+$ cd ltpqhg
+$ ls
+245821 hchndjgj.vht
+229181 rcfmhrqm.ftc
+214977 vgdsjg.jpd
+124547 zgwwvb.pcs
+$ cd ..
+$ cd wzvjft
+$ ls
+dir fdntdf
+174465 pcg.wnr
+80888 qchfgv
+82987 rqbzbrlv
+$ cd fdntdf
+$ ls
+79808 cmlt.cvd
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd jtjv
+$ ls
+262350 zww.fbl
+$ cd ..
+$ cd mgfwthq
+$ ls
+32365 gjq.rpz
+$ cd ..
+$ cd zhq
+$ ls
+dir clvljpb
+dir dfdbzzz
+dir lqhfbp
+152633 nfngbl.mcn
+$ cd clvljpb
+$ ls
+72966 scs
+$ cd ..
+$ cd dfdbzzz
+$ ls
+206453 cgrdn.dcw
+$ cd ..
+$ cd lqhfbp
+$ ls
+141515 nlvswpcm.fvm
+68018 zgwwvb.pcs
+215903 zlmdlbdp
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd msczpj
+$ ls
+dir clvljpb
+dir smhsm
+dir zhq
+$ cd clvljpb
+$ ls
+148686 fmd
+244875 mhnlcz
+271194 qchfgv
+$ cd ..
+$ cd smhsm
+$ ls
+219572 ptzhr
+$ cd ..
+$ cd zhq
+$ ls
+46118 qzmbgv.npf
+$ cd ..
+$ cd ..
+$ cd mvbhn
+$ ls
+dir dnbmm
+17522 dnbmm.hqp
+dir hws
+dir hwtsjfbb
+dir hzqlb
+dir mghrhcsj
+dir mprvjd
+180207 qchfgv
+dir qzrshw
+130436 rdgndm.clf
+128601 tbdz.bgs
+dir vpp
+$ cd dnbmm
+$ ls
+dir jqv
+dir lcclc
+25762 rfwdnjzz.stw
+172833 rpf.vqn
+18217 zgwwvb.pcs
+$ cd jqv
+$ ls
+dir cpbr
+$ cd cpbr
+$ ls
+59543 mclpq.bpr
+$ cd ..
+$ cd ..
+$ cd lcclc
+$ ls
+139444 jpwdgvb.wgz
+$ cd ..
+$ cd ..
+$ cd hws
+$ ls
+42332 clvljpb
+240502 clvljpb.bbn
+dir jdz
+37624 pcg.wnr
+dir pjd
+169282 plw.frm
+100105 tmpll.gwm
+$ cd jdz
+$ ls
+dir dnbmm
+$ cd dnbmm
+$ ls
+191941 cvhvq.rzr
+$ cd ..
+$ cd ..
+$ cd pjd
+$ ls
+dir bnwjc
+dir pgvzhl
+33261 rvpw.jlj
+dir zhq
+$ cd bnwjc
+$ ls
+159772 lqcbv.mvh
+$ cd ..
+$ cd pgvzhl
+$ ls
+159506 nfngbl.mcn
+114670 qchfgv
+$ cd ..
+$ cd zhq
+$ ls
+162563 mtcd
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd hwtsjfbb
+$ ls
+dir clvljpb
+dir fqclffr
+dir hzqlb
+243079 rqbh.ltt
+dir wtz
+$ cd clvljpb
+$ ls
+42146 bbb
+$ cd ..
+$ cd fqclffr
+$ ls
+160031 zgwwvb.pcs
+$ cd ..
+$ cd hzqlb
+$ ls
+70936 pcg.wnr
+230600 pfnfjqc.bsp
+154358 plw.frm
+106007 qtztf
+$ cd ..
+$ cd wtz
+$ ls
+265666 nfngbl.mcn
+dir wjsrb
+dir zhh
+$ cd wjsrb
+$ ls
+76239 wqzg
+$ cd ..
+$ cd zhh
+$ ls
+11571 wptzslq.gwr
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd hzqlb
+$ ls
+199430 gwgrtw.dzv
+$ cd ..
+$ cd mghrhcsj
+$ ls
+49307 bvtmfj.dbh
+$ cd ..
+$ cd mprvjd
+$ ls
+dir zhq
+$ cd zhq
+$ ls
+225705 nfngbl.mcn
+204180 pcg.wnr
+$ cd ..
+$ cd ..
+$ cd qzrshw
+$ ls
+dir ddgs
+dir hzqlb
+dir lmtfhtd
+157122 qchfgv
+dir sjq
+dir tdjh
+$ cd ddgs
+$ ls
+174192 dvb
+100076 rgdbsfbm.wrd
+18400 zgwwvb.pcs
+$ cd ..
+$ cd hzqlb
+$ ls
+165950 plw.frm
+$ cd ..
+$ cd lmtfhtd
+$ ls
+dir clvljpb
+137957 dnbmm.vjs
+159982 lgll.lnp
+25796 plw.frm
+201565 znj.ljv
+$ cd clvljpb
+$ ls
+248187 fdvbtnvh.gsc
+$ cd ..
+$ cd ..
+$ cd sjq
+$ ls
+dir dnbmm
+167394 dzmj
+143508 plw.frm
+dir sllcrmp
+dir ttltfz
+140530 vdsvw.jhv
+$ cd dnbmm
+$ ls
+224433 qchfgv
+$ cd ..
+$ cd sllcrmp
+$ ls
+47580 hfvh.ncs
+dir hgtm
+237683 nzjzd.zcw
+$ cd hgtm
+$ ls
+194211 nsddmsvq
+8615 zgwwvb.pcs
+$ cd ..
+$ cd ..
+$ cd ttltfz
+$ ls
+249866 gbqptvn.pvm
+205314 jjb.qbl
+$ cd ..
+$ cd ..
+$ cd tdjh
+$ ls
+266400 clvljpb.tmv
+130599 qdnmmh.trp
+$ cd ..
+$ cd ..
+$ cd vpp
+$ ls
+214035 nfngbl.mcn
+$ cd ..
+$ cd ..
+$ cd ttjbnj
+$ ls
+dir crlhpd
+47864 dnbmm
+dir ttltfz
+$ cd crlhpd
+$ ls
+dir vmgdpf
+$ cd vmgdpf
+$ ls
+169762 plw.frm
+$ cd ..
+$ cd ..
+$ cd ttltfz
+$ ls
+dir gdf
+dir hdh
+dir jbfwr
+$ cd gdf
+$ ls
+68861 plw.frm
+$ cd ..
+$ cd hdh
+$ ls
+166403 dnbmm
+$ cd ..
+$ cd jbfwr
+$ ls
+100770 pcg.wnr
+178623 wnswp
+41069 zmrrmdv.bzr
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd ttltfz
+$ ls
+234321 dnbmm
+131214 dtpprnwf.hfr
+$ cd ..
+$ cd vjj
+$ ls
+112879 pgzrb
+$ cd ..
+$ cd zhq
+$ ls
+147979 clvljpb
+dir dvm
+136916 pcg.wnr
+205323 rwnrfrph
+$ cd dvm
+$ ls
+dir cpsqlvbl
+dir ffw
+dir hzqlb
+95516 pcg.wnr
+60101 tcswqq.zjf
+$ cd cpsqlvbl
+$ ls
+dir hzqlb
+$ cd hzqlb
+$ ls
+169253 nscj
+$ cd ..
+$ cd ..
+$ cd ffw
+$ ls
+161525 bpg.rsw
+50629 dnbmm.qff
+126458 pcg.wnr
+18268 trvcmp
+dir vwnlb
+171750 zgwwvb.pcs
+dir zhq
+$ cd vwnlb
+$ ls
+218994 ccjz.qrm
+268399 srwv
+$ cd ..
+$ cd zhq
+$ ls
+150894 ztcw.dlc
+$ cd ..
+$ cd ..
+$ cd hzqlb
+$ ls
+45224 fnb.vgg
+53728 nfngbl.mcn
+230460 zhq.bsw
+$ cd ..
+$ cd ..
+$ cd ..
+$ cd zqgcbnrt
+$ ls
+91447 bdjbn
+$ cd ..
+$ cd ..
+$ cd wbvcf
+$ ls
+dir dzh
+$ cd dzh
+$ ls
+250311 qrvn.bft
+$ cd ..
+$ cd ..
+$ cd wsqvpp
+$ ls
+96530 jwhtlzcm.gmq
+$ cd ..
+$ cd ..
+$ cd zcvfqn
+$ ls
+264037 hzqlb.jfp
+dir nlnl
+96691 qchfgv
+126674 zhq.ndc
+$ cd nlnl
+$ ls
+248407 nfngbl.mcn
+188078 pzwmrfht.dfs
+268160 qchfgv
+$ cd ..
+$ cd ..
+$ cd zhq
+$ ls
+91941 bgc.grv
+$ cd ..
+$ cd zpb
+$ ls
+dir dnbmm
+dir fsw
+$ cd dnbmm
+$ ls
+260358 lcpg
+dir lfm
+$ cd lfm
+$ ls
+227028 qchfgv
+$ cd ..
+$ cd ..
+$ cd fsw
+$ ls
+dir fffpsrvp
+153630 pcg.wnr
+dir qtwvgmtl
+2971 qzl.pcn
+17259 zrpl.hcc
+$ cd fffpsrvp
+$ ls
+dir gflwnfc
+176446 lwz.pgq
+$ cd gflwnfc
+$ ls
+132820 cjznqwf.hhq
+224464 nfngbl.mcn
+104803 qchfgv
+$ cd ..
+$ cd ..
+$ cd qtwvgmtl
+$ ls
+dir rcssfd
+$ cd rcssfd
+$ ls
+56266 htr.chf
+128262 qcfsth.mlt
+120527 sqrb
diff --git a/day07/sample b/day07/sample
new file mode 100644
index 0000000..09a921e
--- /dev/null
+++ b/day07/sample
@@ -0,0 +1,23 @@
+$ cd /
+$ ls
+dir a
+14848514 b.txt
+8504156 c.dat
+dir d
+$ cd a
+$ ls
+dir e
+29116 f
+2557 g
+62596 h.lst
+$ cd e
+$ ls
+584 i
+$ cd ..
+$ cd ..
+$ cd d
+$ ls
+4060174 j
+8033020 d.log
+5626152 d.ext
+7214296 k
diff --git a/day07/sol.py b/day07/sol.py
new file mode 100644
index 0000000..e7e4253
--- /dev/null
+++ b/day07/sol.py
@@ -0,0 +1,42 @@
+import sys
+from collections import defaultdict
+cmds = open("input").read().split("$")
+
+cwd = []
+sizes = defaultdict(lambda: 0)
+for cmd in cmds:
+    cmd = cmd.strip()
+    if not cmd:
+        continue
+    print(cmd)
+    if cmd.startswith("cd "):
+        dir = cmd.split()[1]
+        if dir == "..":
+            cwd.pop()
+        elif dir == "/":
+            cwd = []
+        else:
+            cwd.append(dir)
+    elif cmd.startswith("ls\n"):
+        files = cmd.splitlines()[1:]
+        for file in files:
+            sz, name = file.split()
+            if sz == 'dir':
+                pass
+            else:
+                print(cwd, name, sizes)
+                for i in range(len(cwd)+1):
+                    sizes['/'.join(cwd[:i])] += int(sz)
+    else:
+        print("bad command:" +cmd)
+
+
+print(sizes)
+
+t = 0
+for sz in sizes.values():
+    if sz <= 100000:
+        t += sz
+print(t)
+
+print(min(sz for sz in sizes.values() if 70000000 - sizes[''] + sz >= 30000000))