Submission #7461351

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Source Code Expand

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;

//template
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(a);i>(b);i--)
#define ALL(v) (v).begin(),(v).end()
typedef long long int ll; typedef pair<ll, ll> P;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
template<typename A,size_t N,typename T>void Fill(A(&array)[N],const T &val){fill((T*)array, (T*)(array+N), val);}
const int inf = INT_MAX / 2; const ll INF = LLONG_MAX / 2;
//template end

double C[110][110]={},pw[110],dp[110]={};
double f(int r,int s,int p){
    return C[r+s+p][r]*C[s+p][s]*pw[r+s+p];
}

int main(){
    int n; scanf("%d",&n);
    rep(i,0,110){
        C[i][0]=C[i][i]=1;
        rep(j,1,i)C[i][j]=C[i-1][j]+C[i-1][j-1];
    }
    pw[0]=1.0;
    rep(i,1,110)pw[i]=pw[i-1]*1.0/3;
    rep(m,2,n+1){
        double sum[110]={},lop=0;
        rep(r,0,m+1)rep(s,0,m+1-r){
            int p=m-r-s;
            double pp=f(r,s,p);
            int mi=inf,cnt=0,a[]={r,s,p},idx=-1;
            rep(i,0,3)if(a[i]){
                cnt++; chmin(mi,a[i]);
            }
            if(cnt==1){
                lop+=pp; continue;
            } cnt=0;
            rep(i,0,3){
                if(a[i]==mi)cnt++;
                else idx=i;
            }
            if(cnt==1)sum[mi]+=pp;
            else if(cnt==3)lop+=pp;
            else sum[a[(idx+1)%3]]+=pp;
        }
        rep(i,2,m)dp[m]+=dp[i]*sum[i];
        dp[m]=(dp[m]+lop+1.0-lop)/(1.0-lop);
    }
    printf("%.12f\n",dp[n]);
    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:22:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     int n; scanf("%d",&n);
                          ^

Judge Result