graphPartition.cpp

#include "metis.h"

#include <vector>

#include <iostream>

#include <fstream>

#include <string>

#include <sstream>

using namespace std;

vector<idx_t> func(vector<idx_t> xadj, vector<idx_t> adjncy, vector<idx_t> vwgt) {

idx_t nVertices = xadj.size() - 1; // 节点数

idx_t nEdges = adjncy.size() / 2;    // 边数

idx_t nWeights = 1;

idx_t nParts = 2;    // 子图个数

idx_t objval;

std::vector<idx_t> part(nVertices, 0);

int ret = METIS_PartGraphKway(&nVertices, &nWeights, xadj.data(), adjncy.data(),

vwgt.data(), NULL, NULL, &nParts, NULL,

NULL, NULL, &objval, part.data());

std::cout << ret << std::endl;

for (unsigned part_i = 0; part_i < part.size(); part_i++) {

std::cout << part_i << " " << part[part_i] << std::endl;

}

return part;

}

int main() {

ifstream ingraph("文件路径/graph.txt");

if (!ingraph) {

cout << "打开文件失败！" << endl;

exit(1);//失败退回操作系统   

}

int vexnum, edgenum;

string line;

getline(ingraph, line);

istringstream tmp(line);

tmp >> vexnum >> edgenum;

vector<idx_t> xadj(0);

vector<idx_t> adjncy(0); //点的id从0开始

vector<idx_t> vwgt(0);

idx_t a, w;

for (int i = 0; i < vexnum; i++) {

xadj.push_back(adjncy.size());

getline(ingraph, line);

istringstream tmp(line);

while (tmp >> a >> w) {

adjncy.push_back(a);

vwgt.push_back(w);

}

}

xadj.push_back(adjncy.size());

ingraph.close();

vector<idx_t> part = func(xadj, adjncy, vwgt);

ofstream outpartition("文件路径/partition.txt");

if (!outpartition) {

cout << "打开文件失败！" << endl;

exit(1);

}

for (int i = 0; i < part.size(); i++) {

outpartition << i << " " << part[i] << endl;

}

outpartition.close();

}