zoj 2775 Push Button Lock

#include<iostream>#include<stdio.h>#include<string.h>using namespace std;enum {    SIZ = 12,};long long C[SIZ][SIZ] = {0}; long long L[SIZ][SIZ] = {0}; long long tab[SIZ];long long sum[SIZ];void init(){    int i,j;    for(i=0;i<SIZ;i++)        C[i][0] = 1;    for(i=1;i<SIZ;i++){        for(j=1;j<i;j++){ C[i][j] = C[i-1][j-1] + C[i-1][j];        }        C[i][i] = 1;    }    int f,b;    for(i=1;i<SIZ;i++){        L[i][1] = 1;        for(j=2;j<=i;j++){ L[i][j] = 0; for(f=1, b=i-f;b>=j-1;f++,b--){     L[i][j] += C[i][f] * L[b][j-1]; }        }    }}long long calc(int n){    long long ret = 0;    for(long long i=1;i<=n;i++){        ret += L[n][i];    }    return ret;}void fun(){    int i,j;    for(i=1;i<SIZ;i++){        tab[i] = calc(i);    }    for(i=1;i<SIZ;i++){        sum[i] = 0;        for(j=1;j<=i;j++){ sum[i] += C[i][j] * tab[j];        }    }}int main(){    init(); fun();    int tstcase=0,tstnum;    cin>>tstnum;    int n;    while(tstcase ++ < tstnum){        cin>>n;        cout<<tstcase<<" "<<n<<" "<<sum[n]<<endl;    }    return 0;}