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added Fractional Knapsack

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	`1`	`+# Fractional Knapsack`
	`2`	`+`
	`3`	`+## Problem:`
	`4`	`+`
	`5`	+Given `weights`: list of weights where `weights[i]` represents the weight of `i-th` item,
	`6`	+`values` : list of values where `values[i]` represents the value of `i-th` item,
	`7`	+and `capacity`, total weight available,
	`8`	`+Find the maximum values that can be achieved within the limit of total weight.`
	`9`	`+`
	`10`	`+Unlike, 0-1 Knapsack Problem, a fraction/portion of an item can be used`
	`11`	`+`
	`12`	`+## Example:`
	`13`	`+`
	`14`	+```
	`15`	`+weights = [1,2,3]`
	`16`	`+values = [6,10,12]`
	`17`	`+capacity = 5`
	`18`	`+`
	`19`	`+Output: 24`
	`20`	`+Explanation: Whole of first two items and 2/3 of the last item`
	`21`	`+ weight = 1+2+(2/3)*3 = 5`
	`22`	`+ value = 6+10+(2/3)*12 = 24`
	`23`	+```
	`24`	`+`
	`25`	`+## Note:`

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	`1`	`+from collections import defaultdict`
	`2`	`+`
	`3`	`+`
	`4`	`+def fractionalKnapsack(weights, values, capacity):`
	`5`	`+ maxValue = 0`
	`6`	`+ unitValues = defaultdict(int)`
	`7`	`+ for i in range(len(weights)):`
	`8`	`+ unitValues[values[i]/weights[i]] += weights[i]`
	`9`	`+ while capacity:`
	`10`	`+ valueToAdd = max(unitValues)`
	`11`	`+ weightToAdd = min(capacity, unitValues[valueToAdd])`
	`12`	`+ maxValue += valueToAdd * weightToAdd`
	`13`	`+ unitValues[valueToAdd] -= weightToAdd`
	`14`	`+ if unitValues[valueToAdd] == 0:`
	`15`	`+ del unitValues[valueToAdd]`
	`16`	`+ capacity -= weightToAdd`
	`17`	`+ return maxValue`
	`18`	`+`
	`19`	`+`
	`20`	`+weights = [2, 1, 3]`
	`21`	`+values = [10, 6, 12]`
	`22`	`+capacity = 5`
	`23`	`+print(fractionalKnapsack(weights, values, capacity))`

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`@@ -86,6 +86,7 @@ Languages used: Java and Python`
`86`	`86`
`87`	`87`	`- [Assign Cookies](Greedy/AssignCookies)`
`88`	`88`	`- [Car Pooling](Greedy/CarPooling)`
	`89`	`+- [Fractional Knapsack](Greedy/FractionalKnapsack)`
`89`	`90`	`- [Maximize Sum after K Negations](Greedy/MaximizeSumAfterKNegations)`
`90`	`91`	`- [Maximum Score Words](Greedy/MaximumScoreWords)`
`91`	`92`	`- [Score After Flipping Matrix](Greedy/ScoreAfterFlippingMatrix)`

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