...一开始用了三维的...甚至尝试把它搞成二维的...后来发现根本没法转移呀...
既然dalao说这是初中题，那它就算是一道初中题吧...
dp[i][j][k][p]表示当前有i个男生j个女生，男生比女生k个，女生比男生多p个
然后就没有然后了...
1 #include<cstdio> 2 #include<queue> 3 #include<iostream> 4 #include<cstring> 5 #define Ha 12345678 6 using namespace std; 7 inline int abs(int x){if(x>0) return x;return -x;} 8 inline int read(){ 9 int ans=0,f=1;char chr=getchar(); 10 while(!isdigit(chr)){if(chr=='-') f=-1;chr=getchar();} 11 while(isdigit(chr)){ans=(ans<<3)+(ans<<1)+chr-48;chr=getchar();} 12 return ans*f; 13 }int n,m,K,f[155][155][25][25],ans; 14 int main(){ 15 // freopen("1037.in","r",stdin); 16 // freopen("1037.out","w",stdout); 17 n=read(),m=read(),K=read(); 18 f[0][0][0][0]=1; 19 for(int i=0;i<=n;i++)for(int j=0;j<=m;j++)for(int k=0;k<=K;k++)for(int p=0;p<=K;p++) 20 f[i+1][j][k+1][max(p-1,0)]=(f[i+1][j][k+1][max(p-1,0)]+f[i][j][k][p])%Ha,f[i][j+1][max(k-1,0)][p+1]=(f[i][j+1][max(k-1,0)][p+1]+f[i][j][k][p])%Ha; 21 for(int i=0;i<=K;i++)for(int j=0;j<=K;j++) 22 ans=(ans+f[n][m][i][j])%Ha; 23 return cout<<ans,0; 24 }