Greater Than Minimum Property
if a > minimum value of stack xs, then minimum value of stack [ a, xs ] = minimum value of stack xs
If we know that some value a is greater than the minimum value of some list, then the minimum value of the list that includes a is the minimum value of the original list.
Examples
if 7 > minimum value of stack [ 5, [ ] ], then minimum value of stack [ 7, [ 5, [ ] ] ] = minimum value of stack [ 5, [ ] ]
if 10 > minimum value of stack [ 2, [ 3, [ 4, [ ] ] ] ], then minimum value of stack [ 10, [ 2, [ 3, [ 4, [ ] ] ] ] ] = minimum value of stack [ 2, [ 3, [ 4, [ ] ] ] ]
if 5248 > minimum value of stack [ 1000, [ 2300, [ 450, [ ] ] ] ], then minimum value of stack [ 5248, [ 1000, [ 2300, [ 450, [ ] ] ] ] ] = minimum value of stack [ 1000, [ 2300, [ 450, [ ] ] ] ]
If we know the minimum value of some list, this property can tell us the minimum value of a new larger list. This allows us to prove claims about minimum values.
For instance, in the first example, we know that the minimum of the list [5, []] is simply 5. Then, since 7 is greater than 5, we claim that the minimum of [7, [5,[]]] is 5.
If y is greater than the minimum value of list [12, [3, [7, []]]], then what is the minimum value of list [y, [12, [3, [7, []]]]] ?
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