Ural 1073 Square Country

Problem Description

There live square people in a square country. Everything in this country is square also. Thus, the Square Parliament has passed a law about a land. According to the law each citizen of the country has a right to buy land. A land is sold in squares, surely. Moreover, a length of a square side must be a positive integer amount of meters. Buying a square of land with a side a one pays a ² quadrics (a local currency) and gets a square certificate of a landowner.

One citizen of the country has decided to invest all of his N quadrics into the land. He can, surely, do it, buying square pieces 1 × 1 meters. At the same time the citizen has requested to minimize an amount of pieces he buys: "It will be easier for me to pay taxes,"  he has said. He has bought the land successfully.

Your task is to find out a number of certificates he has gotten.

 

Input

The only line contains a positive integer N ≤ 60 000 , that is a number of quadrics that the citizen has invested.

 

Output

The only line contains a number of certificates that he has gotten.

 

Sample Input

input	output
344	3

 

完全背包~

 

 1 #include <stdio.h>
 2 #include <iostream>
 3 #define inf 0x3f3f3f3f
 4 using namespace std;
 5 int main()
 6 {
 7     int dp[60001];
 8     int n;
 9     while( scanf("%d",&n)!=EOF ){
10         for(int i=1; i<=n; i++){
11             dp[i]=inf;
12         }
13         for(int i=0; i*i<=n; i++){
14             for(int j=i*i; j<=n; j++){
15                 dp[j]=min(dp[j-i*i]+1,dp[j]);
16             }
17         }
18         printf("%d\n",dp[n]);
19     }
20     return 0;
21 }