Ignatius and the Princess III
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 10143 Accepted Submission(s): 7184
"The second problem is, given an positive integer N, we define an equation like this:
N=a[1]+a[2]+a[3]+...+a[m];
a[i]>0,1<=m<=N;
My question is how many different equations you can find for a given N.
For example, assume N is 4, we can find:
4 = 4;
4 = 3 + 1;
4 = 2 + 2;
4 = 2 + 1 + 1;
4 = 1 + 1 + 1 + 1;
so the result is 5 when N is 4. Note that "4 = 3 + 1" and "4 = 1 + 3" is the same in this problem. Now, you do it!"
#include<iostream>
#include<cstring>
using namespace std;
int num[130];
int dp[130][130];
int main()
{
int n;
int i,j,k;
while(cin>>n)
{
memset(dp,0,sizeof(dp));
dp[0][0]=1;
for(i=1;i<=n;i++)
{
num[i]=i;
}
for(i=1;i<=n;i++)
{
for(j=0;j<=n;j++)
{
dp[i][j]=dp[i-1][j];
for(k=1;k*num[i]<=j;k++)
{
dp[i][j]=dp[i][j]+dp[i-1][j-k*num[i]];
}
}
}
cout<<dp[n][n]<<endl;
}
return 0;
}