1 |
1. T : Type
2. l : T List
3. x : T
4. i,j: . i<||l||+1 ![](FONT/eq.png) j<||l||+1 ![](FONT/eq.png) i = j ![](FONT/eq.png) [x / l][i] = [x / l][j]
5. i :
6. j :
7. i<||l||
8. j<||l||
9. i = j
l[i] = l[j]
![](FONT/BLANK.png) | 2 steps |
2 |
1. T : Type
2. l : T List
3. x : T
4. i,j: . i<||l||+1 ![](FONT/eq.png) j<||l||+1 ![](FONT/eq.png) i = j ![](FONT/eq.png) [x / l][i] = [x / l][j]
(x l)
![](FONT/BLANK.png) | 3 steps |
3 |
1. T : Type
2. l : T List
3. x : T
4. i,j: . i<||l|| ![](FONT/eq.png) j<||l|| ![](FONT/eq.png) i = j ![](FONT/eq.png) l[i] = l[j]
5. (x l)
6. i :
7. j :
8. i<||l||+1
9. j<||l||+1
10. i = j
[x / l][i] = [x / l][j]
![](FONT/BLANK.png) | 1 step |