Language: C++

#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("Ofast")
#pragma GCC optimize(3)
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC target("sse3","sse2","sse")
#pragma GCC target("avx","sse4","sse4.1","sse4.2","ssse3")
#pragma GCC target("f16c")
#pragma GCC optimize("inline","fast-math","unroll-loops","no-stack-protector")
#pragma GCC diagnostic error "-fwhole-program"
#pragma GCC diagnostic error "-fcse-skip-blocks"
#pragma GCC diagnostic error "-funsafe-loop-optimizations"
#pragma GCC diagnostic error "-std=c++14"
#include "bits/stdc++.h"
//#include "ext/pb_ds/tree_policy.hpp"
//#include "ext/pb_ds/assoc_container.hpp"
#define PB push_back
#define PF push_front
#define LB lower_bound
#define UB upper_bound
#define fr(x) freopen(x,"r",stdin)
#define fw(x) freopen(x,"w",stdout)
#define iout(x) printf("%d\n",x)
#define lout(x) printf("%lld\n",x)
#define REP(x,l,u) for(ll x = l;x<u;x++)
#define RREP(x,l,u) for(ll x = l;x>=u;x--)
#define complete_unique(a) a.erase(unique(a.begin(),a.end()),a.end())
#define mst(x,a) memset(x,a,sizeof(x))
#define all(a) a.begin(),a.end()
#define PII pair<int,int>
#define PLL pair<ll,ll>
#define MP make_pair
#define sqr(x) ((x)*(x))
#define lowbit(x) (x&(-x))
#define lson (ind<<1)
#define rson (ind<<1|1)
#define se second
#define fi first
#define dbg(x) cerr<<#x<<" = "<<(x)<<endl;
#define sz(x) ((int)x.size())
#define EX0 exit(0);

typedef  long long ll;
typedef unsigned long long ull;
typedef long double db;
typedef long double ld;
using namespace std;
typedef vector<ll> VLL;
typedef vector<int> VI;
const int block_size = 320;
typedef complex<ll> point;
const ll mod = 1e9+7;
const ll inf = 1e9+7;
const ld eps = 1e-9;
const db PI = atan(1)*4;
template<typename T>
inline int sign(const T&a) {
    if(a<0)return -1;
    if(a>0)return 1;
    return 0;
}

template<typename T,typename S>inline bool upmin(T&a,const S&b){return a>b?a=b,1:0;}
template<typename T,typename S>inline bool upmax(T&a,const S&b){return a<b?a=b,1:0;}

template<typename T> inline void in(T &x) {
    x = 0;
    T f = 1;
    char ch = getchar();
    while (!isdigit(ch)) {
        if (ch == '-') f = -1;
        ch = getchar();
    }
    while (isdigit(ch))  {
        x = x * 10 + ch - '0';
        ch = getchar();
    }
    x *= f;
}

ll twop(int x) {
    return 1LL<<x;
}

template<typename A,typename B > inline void in(A&x,B&y) {
    in(x);
    in(y);
}
template<typename A,typename B,typename C>inline void in(A&x,B&y,C&z) {
    in(x);
    in(y);
    in(z);
}
template<typename A,typename B,typename C,typename D> inline void in(A&x,B&y,C&z,D&d) {
    in(x);
    in(y);
    in(z);
    in(d);
}

namespace SOLVE {
    void main(){
    }
}
PLL operator-(const PLL&a,const PLL&b){
    return MP(a.fi-b.fi,a.se-b.se);
}

ll cp(PLL o,PLL a,PLL b){
    a = a-o;b = b-o;
    return a.fi*b.se-a.se*b.fi;
}

ll ip(PLL o,PLL a,PLL b){
    a = a-o;b = b-o;
    return a.fi*b.fi+a.se*b.se;
}



db norm(PLL x){
    return sqrt(sqr(x.fi)+sqr(x.se));
}



db ans[1000000];
int main() {

    
    
    
    
    
    
    
    
    int n;in(n);
    deque<pair<PLL, int> >U,L;
    REP(i,0,n){
        pair<PLL, int>tmp;;
        cin>>tmp.fi.fi>>tmp.fi.se;
        tmp.se = i;
        U.PB(tmp);
    }
    
    sort(all(U));L = U;
    deque<pair<PLL, int> >tmp;
    for(auto i:U){
        if(sz(tmp)<=1)tmp.PB(i);
        else{
            while (sz(tmp) >= 2 &&cp(tmp[sz(tmp)-2].fi, tmp[sz(tmp)-1].fi, i.fi) >= 0) {
                tmp.pop_back();
            }
            tmp.PB(i);
        }
    }
    U = tmp;
    tmp.clear();
    for(auto i:L){
        if(sz(tmp)<=1)tmp.PB(i);
        else{
            while (sz(tmp) >= 2 && cp(tmp[sz(tmp)-2].fi, tmp[sz(tmp)-1].fi, i.fi) <= 0) {
                tmp.pop_back();
            }
            tmp.PB(i);
        }
    }
    L = tmp;

    RREP(i,sz(L)-2,1){
        U.PB(L[i]);
    }
    {
        auto a = U.front(),b = U.back();
        U.PF(b);
        U.PB(a);
        
        REP(i,1,sz(U)-1){
            cerr<<U[i].se<<endl;
            dbg(norm(U[i].fi-U[i-1].fi)*norm(U[i].fi-U[i+1].fi));
            ans[U[i].se] = PI-acos(ip(U[i].fi, U[i-1].fi, U[i+1].fi)/(norm(U[i].fi-U[i-1].fi)*norm(U[i].fi-U[i+1].fi)));
          	if(U[i-1] == U[i+1])ans[U[i].se] = 0.5.  
          dbg(ans[U[i].se]/(2*PI)*360);
        }
    }
    dbg(acos(1/2));
    REP(i,0,n)cout<<setprecision(20)<<ans[i]/(2*PI)<<endl;
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    return 0;
}


Compiler output:
a.cc:182:52: error: too many decimal points in number
  182 |                 if(U[i-1] == U[i+1])ans[U[i].se] = 0.5.
      |                                                    ^~~~
a.cc:9:30: warning: '-fwhole-program' is not an option that controls warnings [-Wpragmas]
    9 | #pragma GCC diagnostic error "-fwhole-program"
      |                              ^~~~~~~~~~~~~~~~~
a.cc:10:30: warning: '-fcse-skip-blocks' is not an option that controls warnings [-Wpragmas]
   10 | #pragma GCC diagnostic error "-fcse-skip-blocks"
      |                              ^~~~~~~~~~~~~~~~~~~
a.cc:11:30: warning: '-funsafe-loop-optimizations' is not an option that controls warnings [-Wpragmas]
   11 | #pragma GCC diagnostic error "-funsafe-loop-optimizations"
      |                              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
a.cc:12:30: warning: '-std=c++14' is not an option that controls warnings [-Wpragmas]
   12 | #pragma GCC diagnostic error "-std=c++14"
      |                              ^~~~~~~~~~~~