49 lines
861 B
C++
49 lines
861 B
C++
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/*
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Description: C++ program to find product of 2 numbers using Recursion.
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Approach: Product of two numbers (x,y) can be defined as y times sum of x.
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Calling the function recursively y times and adding x to it.
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Time Complexity: O(n) where n is the value of y
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*/
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#include <bits/stdc++.h>
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using namespace std;
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// recursive function to calculate multiplication of two numbers
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int product(int x, int y)
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{
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// if x is less than
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// y swap the numbers
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if (x < y)
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return product(y, x);
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// iteratively calculate
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// y times sum of x
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else if (y != 0)
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return (x + product(x, y - 1));
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// if any of the two numbers is
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// zero return zero
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else
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return 0;
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}
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int main()
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{
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int x = 5, y = 2;
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cout << product(x, y);
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return 0;
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}
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/*
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Sample Input:
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x=5, y=2
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Output: 10
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Sample Input:
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x=6, y=7
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Output: 42
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*/
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