整数划分问题

dp优化:

#include 
using namespace std;

const int N = 1010, MOD = 1e9 + 7;
int dp[N];

int main()
{
int n; cin >> n;
    dp[0] = 1;
    for(int i = 1; i <= n; i ++ ){
        for(int j = i; j <= n; j ++ ){
            dp[j]+=dp[j-i];
        }
    }
    cout << dp[n] << endl;
    return 0;
}