给出C++代码,采用模拟退火算法,流水车间调度问题可以描述为 n 个工件要在 m 台机器上加工,每个工件需要经过 m 道工序,每道工序要求不同的机器加工,每个机器同时只能加工一个工件,一个工件不能同时在不同的机器上加工。工件在机器上的加工时间是给定的。 问题的目标是求n个工件的加工顺序,使总完工时间达到最小。,
时间: 2023-09-12 13:05:06 浏览: 84
以下是采用模拟退火算法解决流水车间调度问题的C++代码:
```c++
#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <ctime>
using namespace std;
// 工件
struct Job {
int id; // 工件编号
vector<int> time; // 每道工序的加工时间
};
// 机器
struct Machine {
int id; // 机器编号
int time; // 机器加工时间
int jobId; // 当前加工的工件编号
int jobStep; // 当前工件的工序
};
// 计算总完工时间
int calcTotalTime(vector<Job>& jobs, vector<Machine>& machines) {
int totalTime = 0;
for (int i = 0; i < jobs.size(); i++) {
int jobTime = 0;
for (int j = 0; j < jobs[i].time.size(); j++) {
int machineId = j;
int machineTime = jobs[i].time[j];
int currTime = machines[machineId].time;
if (machines[machineId].jobId != -1 && machines[machineId].jobId != i) {
currTime = max(currTime, machines[machineId].time + jobs[machines[machineId].jobId].time[machines[machineId].jobStep]);
}
jobTime += currTime - machines[machineId].time;
machines[machineId].time = currTime + machineTime;
machines[machineId].jobId = i;
machines[machineId].jobStep = j;
}
totalTime = max(totalTime, jobTime);
}
return totalTime;
}
// 生成初始解
vector<int> generateInitSolution(int n) {
vector<int> solution(n);
for (int i = 0; i < n; i++) {
solution[i] = i;
}
random_shuffle(solution.begin(), solution.end());
return solution;
}
// 生成邻域解
vector<int> generateNeighbourSolution(vector<int>& solution) {
int n = solution.size();
int i = rand() % n;
int j = rand() % n;
while (i == j) {
j = rand() % n;
}
swap(solution[i], solution[j]);
return solution;
}
// 模拟退火算法
vector<int> simulatedAnnealing(vector<Job>& jobs, vector<Machine>& machines, double T0, double T1, double r) {
int n = jobs.size();
vector<int> currSolution = generateInitSolution(n);
vector<int> bestSolution = currSolution;
int currCost = calcTotalTime(jobs, machines);
int bestCost = currCost;
double T = T0;
while (T > T1) {
for (int i = 0; i < 100; i++) {
vector<int> newSolution = generateNeighbourSolution(currSolution);
int newCost = calcTotalTime(jobs, machines);
int delta = newCost - currCost;
if (delta <= 0 || exp(-delta / T) > ((double) rand()) / RAND_MAX) {
currSolution = newSolution;
currCost = newCost;
if (currCost < bestCost) {
bestSolution = currSolution;
bestCost = currCost;
}
}
}
T *= r;
}
return bestSolution;
}
int main() {
srand(time(NULL));
int n, m;
cin >> n >> m;
vector<Job> jobs(n);
for (int i = 0; i < n; i++) {
jobs[i].id = i;
jobs[i].time.resize(m);
for (int j = 0; j < m; j++) {
cin >> jobs[i].time[j];
}
}
vector<Machine> machines(m);
for (int i = 0; i < m; i++) {
machines[i].id = i;
machines[i].time = 0;
machines[i].jobId = -1;
machines[i].jobStep = -1;
}
double T0 = 10000;
double T1 = 1;
double r = 0.95;
vector<int> solution = simulatedAnnealing(jobs, machines, T0, T1, r);
cout << "最优解为:";
for (int i = 0; i < n; i++) {
cout << solution[i] << " ";
}
cout << endl;
cout << "最小完工时间为:" << calcTotalTime(jobs, machines) << endl;
return 0;
}
```
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