算法导论 ch15 动态规划 任务调度

1. souce codes

 

#include <iostream> using namespace std; void fastestWay(int a[][6], int t[][5], int e[2], int x[2], int n) { int f[2][6]; int l[2][6]; int fstar = 0; int lstar = 0; f[0][0] = e[0] + a[0][0]; f[1][0] = e[1] + a[1][0]; for (int j = 1; j < n; j++) { if (f[0][j - 1] + a[0][j]<= f[1][j - 1] + t[1][j-1]+ a[0][j]) { f[0][j] = f[0][j - 1] + a[0][j]; l[0][j] = 0; } else { f[0][j] = f[1][j - 1] + t[1][j-1]+ a[0][j]; l[0][j] = 1; } if (f[1][j - 1] + a[1][j]<= f[0][j - 1] + t[0][j-1]+ a[1][j]) { f[1][j] = f[1][j - 1] + a[1][j]; l[1][j] = 1; } else { f[1][j] = f[0][j - 1] + t[0][j-1]+ a[1][j]; l[1][j] = 0; } } if (f[0][n - 1] + x[0]<= f[1][n-1] + x[1]) { fstar = f[0][n-1] + x[0]; lstar = 0; } else { fstar = f[1][n-1] + x[1]; lstar = 1; } cout << "fastest way is "<< fstar << ", and line is "<< lstar << endl; cout << endl; cout << "the f table is :"<< endl; for (int i = 0; i < 2; i++) { for (int j = 0; j < n; j++) { cout << f[i][j]<< " "; } cout << endl; } cout << endl; cout << "the l table is :"<< endl; for (int i = 0; i < 2; i++) { for (int j = 1; j < n; j++) { cout << l[i][j]<< " "; } cout << endl; } cout << endl; cout << "the fastest way is :"<< endl; int i = lstar; cout << "line "<< i << ", station "<< n - 1<< endl; for (int j = n - 1; j >= 1; j--) { i = l[i][j]; cout << "line "<< i << ", station "<< j - 1<< endl; } } int main() { // the time for entering line 1 and line 2 int e[2] = { 2, 4 }; // time on line 1 and line 2 int a[2][6] = { { 7, 9, 3, 4, 8, 4 }, { 8, 5, 6, 4, 5, 7 } }; // transfer time on line 1 and line 2 int t[2][5] = { { 2, 3, 1, 3, 4 }, { 2, 1, 2, 2, 1 } }; // exit time on line 1 and line 2 int x[2] = { 3, 2 }; fastestWay(a, t, e, x, 6); }

 

2. test result

 

fastest way is 38, and line is 0 the f table is : 9 18 20 24 32 35 12 16 22 25 30 37 the l table is : 0 1 0 0 1 0 1 0 1 1 the fastest way is : line 0, station 5 line 1, station 4 line 1, station 3 line 0, station 2 line 1, station 1 line 0, station 0