Topic 1027: Euler circuits

Title Description:

The

Euler circuit refers to a loop that does not leave the pen on paper, but only once per side of the picture and can return to the starting point. Now given a diagram, ask if there is a Euler circuit?

Input:

The

test input contains several test cases. The 1th line of each test case gives two positive integers, namely the number of nodes N (1 < N < 1000) and the number of sides m, followed by M-bars, each with a pair of positive integers, the number of two nodes (nodes from 1 to N) that are directly connected to the bar. When n is 0 o'clock, the input ends.

Output:

the output of each test case is one row, or output 1 if the Euler loop is present, otherwise output 0.

Sample input:

3 31 21 32 33 21 22 30

Sample output:

10

Code:

#include <iostream>using namespacestd;inttree[1001];//stores the parent node for each nodeintdegree[1001];//the degree to which each node is stored (no graph) intFindRoot (intx) {    if(tree[x]==-1)        returnx; Else{        inttmp=FindRoot (tree[x]); TREE[X]=tmp; returntmp; }} /*thought: 1. Use and check the set to determine whether it is connected Figure 2. If the given graph is a connected graph, then look at the degree of each node, if the degree of a node is 1, then the "Euler loop" will not be formed.*/ intMain () {intn,m;  while(cin>>N) {        if(n==0)             Break; CIN>>m;  for(intI=1; i<=n;++i) {//Initializetree[i]=-1; Degree[i]=0; }         for(intI=0; i<m;++i) {            intb; CIN>>a>>b; ++Degree[a]; ++Degree[b]; intRoot_a=FindRoot (a); introot_b=FindRoot (b); if(root_a!=root_b) {Tree[root_b]=root_a; }        }        intCnt=0;//Count the number of connected components        BOOLflag=true;  for(intI=1; i<=n;++i) {            if(tree[i]==-1)                ++CNT; }        if(cnt!=1) {cout<<0<<Endl; Flag=false; }        Else{             for(intI=1; i<=n;++i) {                if(degree[i]==1){//See if there is a node with a degree of 1cout<<0<<Endl; Flag=false;  Break; }            }        }        if(flag==true) cout<<1<<Endl; }    return 0;} /************************************************************** problem:1027 User:lcyvino language:c++ Re sult:accepted time:130 Ms memory:1528 kb****************************************************************/

Topic 1027: Euler circuits