Codeforces Testing Round 5
C
Berland Traffic
Codeforces
2700
原题
← B→
翻译中…

Berland traffic is very different from traffic in other countries. The capital of Berland consists of $*n*$ junctions and $*m*$ roads. Each road connects a pair of junctions. There can be multiple roads between a pair of junctions. For each road we know its capacity: value $*c*_{*i*}$ is the maximum number of cars that can drive along a road in any direction per a unit of time. For each road, the cars can drive along it in one of two direction. That it, the cars can't simultaneously move in both directions. A road's traffic is the number of cars that goes along it per a unit of time. For road ($*a*_{*i*}, *b*_{*i*}$) this value is negative, if the traffic moves from $*b*_{*i*}$ to $*a*_{*i*}$. A road's traffic can be a non-integer number.

翻译中…

The capital has two special junctions — the entrance to the city (junction 1) and the exit from the city (junction $*n*$). For all other junctions it is true that the traffic is not lost there. That is, for all junctions except for 1 and $*n*$ the incoming traffic sum equals the outgoing traffic sum.

翻译中…

Traffic has an unusual peculiarity in the capital of Berland — for any pair of junctions ($*x*, *y*$) the sum of traffics along any path from $*x*$ to $*y*$ doesn't change depending on the choice of the path. Such sum includes traffic along all roads on the path (possible with the "minus" sign, if the traffic along the road is directed against the direction of the road on the path from $*x*$ to $*y*$).

翻译中…

Your task is to find the largest traffic that can pass trough the city per one unit of time as well as the corresponding traffic for each road.

翻译中…

Input

翻译中…

The first line contains a positive integer $*n*$ — the number of junctions ($2 ≤ *n* ≤ 100$). The second line contains integer $*m*$ ($1 ≤ *m* ≤ 5000$) — the number of roads. Next $*m*$ lines contain the roads' descriptions. Each road contains a group of three numbers $*a*_{*i*}$, $*b*_{*i*}$, $*c*_{*i*}$, where $*a*_{*i*}, *b*_{*i*}$ are the numbers of junctions, connected by the given road, and $*c*_{*i*}$ ($1 ≤ *a*_{*i*}, *b*_{*i*} ≤ *n*$; $*a*_{*i*} ≠ *b*_{*i*}$; $0 ≤ *c*_{*i*} ≤ 10000$) is the largest permissible traffic along this road.

翻译中…

Output

翻译中…

In the first line print the required largest traffic across the city. Then print $*m*$ lines, on each line print the speed, at which the traffic moves along the corresponding road. If the direction doesn't match the order of the junctions, given in the input, then print the traffic with the minus sign. Print the numbers with accuracy of at least five digits after the decimal point.

翻译中…

If there are many optimal solutions, print any of them.

翻译中…

样例

Input #1
2
3
1 2 2
1 2 4
2 1 1000
Output #1
6.00000
2.00000
2.00000
-2.00000
InputCopy OutputCopy
Input #2
7
11
1 2 7
1 2 7
1 3 7
1 4 7
2 3 7
2 5 7
3 6 7
4 7 7
5 4 7
5 6 7
6 7 7
Output #2
13.00000
2.00000
2.00000
3.00000
6.00000
1.00000
3.00000
4.00000
7.00000
1.00000
2.00000
6.00000
InputCopy OutputCopy
题目信息
题号
267C
时间限制
2 s
内存限制
256 MB
标签
数学
矩阵

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。