提出 #61244382

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ソースコード 拡げる

// Go in my style.
// Not afraid to dark.

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

clock_t sttime;
#define STCLOCK sttime = clock ();
#define TIMENOW fprintf (stderr, "\nNOW TIME COSSEMED: %0.4lf\n", 1.0 * (clock () - sttime) / CLOCKS_PER_SEC);
#define inline __inline__ __attribute__ ((always_inline))

const int N = 2e5;
const long double eps = 1e-11;
int n;
long double a[N + 5], b[N + 5], c[N + 5], f[N + 5];
int sta[N + 5], top;

inline long double Cal (int x, int y, int z){ return a[x] * (y - z) / (y - x) + a[y] * (x - z) / (x - y); }
inline bool Cmp (long double x, long double y){ return (y - x) > eps; }

inline void lbread (long double &x){ double y; scanf ("%lf", &y); x = y; }

signed main (){
    STCLOCK

    scanf ("%d", &n);
    int id = 1;
    for (int i = 1;i <= n;++ i){
        lbread (a[i]);
        if (a[id] < a[i]) id = i;
    }
    for (int i = 1;i <= n;++ i) b[i] = a[(i + id - 2) % n + 1];
    for (int i = 1;i <= n;++ i) a[i] = b[i];
    for (int i = 1;i <= n;++ i) lbread (b[(i - id + n) % n + 1]);
    for (int i = 2;i <= n;++ i) c[2] -= 1.0 * (n + 1 - i) * b[i] * 2;
    a[n + 1] = a[1], b[n + 1] = b[1];
    c[1] = 0; c[2] /= n;
    for (int i = 3;i <= n;++ i) c[i] = c[i - 1] * 2 - c[i - 2] + 2 * b[i - 1];
    for (int i = 2;i <= n;++ i) a[i] -= c[i];
    sta[top = 1] = 1; a[n + 1] = a[1];
    for (int i = 2;i <= n + 1;++ i){
        while (top > 1 && Cmp (a[sta[top]], Cal (sta[top - 1], i, sta[top]))) -- top;
        sta[++ top] = i;
    }
    for (int i = 1;i < top;++ i)
        for (int j = sta[i];j < sta[i + 1];++ j)
            f[j] = Cal (sta[i], sta[i + 1], j) + c[j];
    long double ans = 0;
    for (int i = 1;i <= n;++ i) ans += f[i];
    printf ("%0.14lf\n", (double) (ans / n));

    TIMENOW
    return 0;
}

提出情報

コンパイルエラー

Main.cpp: In function ‘int main()’:
Main.cpp:26:11: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   26 |     scanf ("%d", &n);
      |     ~~~~~~^~~~~~~~~~
Main.cpp: In function ‘void lbread(long double&)’:
Main.cpp:21:54: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   21 | inline void lbread (long double &x){ double y; scanf ("%lf", &y); x = y; }
      |                                                ~~~~~~^~~~~~~~~~~

ジャッジ結果