poj2279 线性dp

#include<iostream>
#include<cstdio>
#include<cstring>
#define ll long long 
using namespace std;
int lim[6];
ll dp[31][31][31][31][31];
int main(){
    int n;
    while(scanf("%d",&n)==1){
        memset(lim,0,sizeof lim);
        memset(dp,0,sizeof dp);
        for(int i=1;i<=n;i++) scanf("%d",&lim[i]);
        dp[0][0][0][0][0]=1;
        for(int i=0;i<=lim[1];i++){
            for(int j=0;j<=lim[2];j++){
                if(j>i)continue;//j>i这种状态不可能成立 
                for(int k=0;k<=lim[3];k++){
                    if(k>j || k>i)continue; 
                    for(int l=0;l<=lim[4];l++){
                        if(l>k||l>j||l>i)continue;
                        for(int m=0;m<=lim[5];m++){
                            if(m>l || m>k || m>j || m>i)continue;
                            if(i+1<=lim[1]) dp[i+1][j][k][l][m]+=dp[i][j][k][l][m];
                            if(j+1<=lim[2]) dp[i][j+1][k][l][m]+=dp[i][j][k][l][m];
                            if(k+1<=lim[3]) dp[i][j][k+1][l][m]+=dp[i][j][k][l][m];
                            if(l+1<=lim[4]) dp[i][j][k][l+1][m]+=dp[i][j][k][l][m];
                            if(m+1<=lim[5]) dp[i][j][k][l][m+1]+=dp[i][j][k][l][m];
                        }
                    }
                }
            }
        }
        printf("%lld\n",dp[lim[1]][lim[2]][lim[3]][lim[4]][lim[5]]);
    }
}