Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Perfect Squares in C++
Suppose we have a positive integer n, find the least number of perfect square numbers whose sum is n. So if the number is 13, then the output is 2, as the numbers are 13 = 9 + 4
To solve this, we will follow these steps −
- create one table for dynamic programming, of length n + 1, and fill it with infinity
- dp[0] := 0
- for i := 1, when i*i <= n
- x = i * i
- for j := x to n
- dp[j] := minimum of dp[j] and 1 + dp[j – x]
- return dp[n]
Let us see the following implementation to get better understanding −
Example
#include <bits/stdc++.h>
using namespace std;
#define INF 1e9
class Solution {
public:
int numSquares(int n) {
vector < int > dp(n+1,INF);
dp[0] = 0;
for(int i =1;i*i<=n;i++){
int x = i*i;
for(int j = x;j<=n;j++){
dp[j] = min(dp[j],1+dp[j-x]);
}
}
return dp[n];
}
};
main(){
Solution ob;
cout << (ob.numSquares(147));
}Input
147
Output
3
Updated on: 04-May-2020
408 Views
Advertisements