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Memoization.js
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Memoization.js
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// this function is going to take a lot of time first this will complete all the loops then return the result
function cube(num){
for(let i = 1; i<=100000; i++){
for(let j = 1; j<=10000; j++){
// heavy-duty work as loops are too big.
}
}
return num**3;
}
undefined
// PROBLEM
// if the function does some heavy-duty work, then, computing the result again and again with the same parameter will lead to wastage of time.
cube(3);
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Window {window: Window, self: Window, document: document, name: '', location: Location, …}
// Good Solution
// This is where memoization comes in, by using memoization we can store(cache) the computed results based on the parameters.
// If the same parameter is used again while invoking the function, instead of computing the result, we directly return the stored (cached) value.
var cache = {}; // we have created object of cache instead array, because object will complete the work in constant time and array will definately took some what n or logn time.
function cube(num){
if(cache[num]){
return cache[num];
}
for(let i = 1; i<=10000; i++){
for(let j = 1; j<=10000; j++){
}
}
cache[num] = num ** 3;
return cache[num];
}
undefined
cube(3); // this will take time to print the result bcz it's printing 1st time
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Window {window: Window, self: Window, document: document, name: '', location: Location, …}
cache;
{3: 27}
cube(3); // instead of computing the result again, it returns the cached result.
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cube(5); // this will take time to print the result bcz it's printing 1st time
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cache; // data in cache memory.
{3: 27, 5: 125}
cube(5); // instead of computing the result again, it returns the cached result.
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