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# 4.4.1 - Dijkstra's algorithm
* 不可有負邊存在
### 1. 演算法
Cost Matrix `C[i][j]`:為一個nxn矩陣，n=|V|
$$C\[i,j]= \begin{cases} 邊長, & \textrm{if (i, j) exists}\ ∞, & \textrm{if (i, j) doesn't exist}\ 0, & \textrm{if i = j} \end{cases}$$
$$S\[i]= \begin{cases} 0, & \textrm{未確定起點到i的shortest path length}\ 1, & \textrm{已確定起點到i的shortest path length} \end{cases}$$
$$Dist\[i]:\textrm{起點到i的shortest path length}$$
$$Dist\[w]=min{Dist\[w],\ Dist\[u]+C\[u,w]}$$
### 2. 範例
求5到各點的最短路徑？
