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Download_Speed.py
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from heapq import *
from collections import *
import os
import sys
sys.setrecursionlimit(1<<30)
from io import BytesIO, IOBase
import math
import bisect
from math import inf
import random
ins = lambda: [int(x) for x in input()]
inp = lambda: int(input())
inps = lambda: [int(x) for x in input().split()]
from fractions import Fraction as F
dc=defaultdict(list)
dc2=defaultdict(list)
class edg:
def __init__(self,u,v,c,r):
self.u=u
self.v=v
self.c=c
self.r=r
def main():
n,m=inps()
e=[]
for i in range(m):
a,b,c=inps()
a-=1
b-=1
e.append(edg(a,b,c,2*i+1))
e.append(edg(b,a,0,2*i))
dc[a].append(2*i)
dc[b].append(2*i+1)
mxf=0
md=pow(10,9)+7
while True:
f=inf
par=[-1]*(n+1)
q=deque([0])
d=[inf]*(n+1)
d[0]=0
while q:
cn=q.popleft()
for ed in dc[cn]:
nbr=e[ed].v
c=e[ed].c
if d[nbr]>md and c>0:
#f=min(f,c)
par[nbr]=ed
#vis[nbr]=1
d[nbr]=1+d[cn]
q.append(nbr)
if d[n-1]>md:
break
cn=n-1
while cn:
f=min(f,e[par[cn]].c)
cn=e[par[cn]].u
mxf+=f
cn=n-1
while cn:
#f=min(f,e[par[cn]].c)
e[par[cn]].c-=f
e[e[par[cn]].r].c+=f
cn=e[par[cn]].u
print(mxf)
BUFSIZE = 8192
class FastIO(IOBase):
newlines = 0
def __init__(self, file):
self._fd = file.fileno()
self.buffer = BytesIO()
self.writable = "x" in file.mode or "r" not in file.mode
self.write = self.buffer.write if self.writable else None
def read(self):
while True:
b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
if not b:
break
ptr = self.buffer.tell()
self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
self.newlines = 0
return self.buffer.read()
def readline(self):
while self.newlines == 0:
b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
self.newlines = b.count(b"\n") + (not b)
ptr = self.buffer.tell()
self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
self.newlines -= 1
return self.buffer.readline()
def flush(self):
if self.writable:
os.write(self._fd, self.buffer.getvalue())
self.buffer.truncate(0), self.buffer.seek(0)
class IOWrapper(IOBase):
def __init__(self, file):
self.buffer = FastIO(file)
self.flush = self.buffer.flush
self.writable = self.buffer.writable
self.write = lambda s: self.buffer.write(s.encode("ascii"))
self.read = lambda: self.buffer.read().decode("ascii")
self.readline = lambda: self.buffer.readline().decode("ascii")
sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip("\r\n")
# endregion
if __name__ == "__main__":
main()
# import threading,sys
# sys.setrecursionlimit(1000000)
# threading.stack_size(1024000)
# thread=threading.Thread(target=main)
# thread.start()