#409906 (C++11) No.955 ax^2+bx+c=0

• 問題: No.955 ax^2+bx+c=0
• ユーザー: ianCK
• 提出日時: 2019-12-18 04:21:27
• 言語: C++11 (gcc 11.4.0)
• 結果: AC
• 実行時間: 3 ms / 2,000 ms
• コード長: 1,738 bytes
• コンパイル時間: 675 ms
• コンパイル使用メモリ: 67,796 KB
• 実行使用メモリ: 4,348 KB
• 最終ジャッジ日時: 2023-10-19 02:09:01
• 合計ジャッジ時間: 3,751 ms
• ジャッジサーバーID （参考情報）: judge15 / judge13

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	3 ms; 4,348 KB
testcase_01	AC	2 ms; 4,348 KB
testcase_02	AC	2 ms; 4,348 KB
testcase_03	AC	2 ms; 4,348 KB
testcase_04	AC	2 ms; 4,348 KB
testcase_05	AC	2 ms; 4,348 KB
testcase_06	AC	2 ms; 4,348 KB
testcase_07	AC	1 ms; 4,348 KB
testcase_08	AC	2 ms; 4,348 KB
testcase_09	AC	2 ms; 4,348 KB
testcase_10	AC	2 ms; 4,348 KB
testcase_11	AC	2 ms; 4,348 KB
testcase_12	AC	2 ms; 4,348 KB
testcase_13	AC	2 ms; 4,348 KB
testcase_14	AC	1 ms; 4,348 KB
testcase_15	AC	2 ms; 4,348 KB
testcase_16	AC	2 ms; 4,348 KB
testcase_17	AC	2 ms; 4,348 KB
testcase_18	AC	1 ms; 4,348 KB
testcase_19	AC	1 ms; 4,348 KB
testcase_20	AC	1 ms; 4,348 KB
testcase_21	AC	1 ms; 4,348 KB
testcase_22	AC	2 ms; 4,348 KB
testcase_23	AC	2 ms; 4,348 KB
testcase_24	AC	2 ms; 4,348 KB
testcase_25	AC	2 ms; 4,348 KB
testcase_26	AC	2 ms; 4,348 KB
testcase_27	AC	1 ms; 4,348 KB
testcase_28	AC	2 ms; 4,348 KB
testcase_29	AC	2 ms; 4,348 KB
testcase_30	AC	2 ms; 4,348 KB
testcase_31	AC	1 ms; 4,348 KB
testcase_32	AC	2 ms; 4,348 KB
testcase_33	AC	1 ms; 4,348 KB
testcase_34	AC	3 ms; 4,348 KB
testcase_35	AC	2 ms; 4,348 KB
testcase_36	AC	3 ms; 4,348 KB
testcase_37	AC	2 ms; 4,348 KB
testcase_38	AC	3 ms; 4,348 KB
testcase_39	AC	3 ms; 4,348 KB
testcase_40	AC	3 ms; 4,348 KB
testcase_41	AC	3 ms; 4,348 KB
testcase_42	AC	2 ms; 4,348 KB
testcase_43	AC	2 ms; 4,348 KB
testcase_44	AC	3 ms; 4,348 KB
testcase_45	AC	3 ms; 4,348 KB
testcase_46	AC	3 ms; 4,348 KB
testcase_47	AC	3 ms; 4,348 KB
testcase_48	AC	3 ms; 4,348 KB
testcase_49	AC	3 ms; 4,348 KB
testcase_50	AC	3 ms; 4,348 KB
testcase_51	AC	3 ms; 4,348 KB
testcase_52	AC	3 ms; 4,348 KB
testcase_53	AC	3 ms; 4,348 KB
testcase_54	AC	3 ms; 4,348 KB
testcase_55	AC	2 ms; 4,348 KB
testcase_56	AC	2 ms; 4,348 KB
testcase_57	AC	3 ms; 4,348 KB
testcase_58	AC	2 ms; 4,348 KB
testcase_59	AC	2 ms; 4,348 KB
testcase_60	AC	2 ms; 4,348 KB
testcase_61	AC	2 ms; 4,348 KB
testcase_62	AC	1 ms; 4,348 KB
testcase_63	AC	1 ms; 4,348 KB
testcase_64	AC	2 ms; 4,348 KB
testcase_65	AC	2 ms; 4,348 KB
testcase_66	AC	1 ms; 4,348 KB
testcase_67	AC	1 ms; 4,348 KB
testcase_68	AC	1 ms; 4,348 KB
testcase_69	AC	1 ms; 4,348 KB
testcase_70	AC	3 ms; 4,348 KB
testcase_71	AC	2 ms; 4,348 KB
testcase_72	AC	1 ms; 4,348 KB
testcase_73	AC	2 ms; 4,348 KB
testcase_74	AC	2 ms; 4,348 KB
testcase_75	AC	1 ms; 4,348 KB
testcase_76	AC	2 ms; 4,348 KB
testcase_77	AC	2 ms; 4,348 KB
testcase_78	AC	2 ms; 4,348 KB
testcase_79	AC	1 ms; 4,348 KB
testcase_80	AC	2 ms; 4,348 KB
testcase_81	AC	1 ms; 4,348 KB
testcase_82	AC	2 ms; 4,348 KB
testcase_83	AC	2 ms; 4,348 KB
testcase_84	AC	1 ms; 4,348 KB
testcase_85	AC	2 ms; 4,348 KB
testcase_86	AC	2 ms; 4,348 KB
testcase_87	AC	2 ms; 4,348 KB
testcase_88	AC	2 ms; 4,348 KB
testcase_89	AC	2 ms; 4,348 KB
testcase_90	AC	1 ms; 4,348 KB
testcase_91	AC	2 ms; 4,348 KB
testcase_92	AC	2 ms; 4,348 KB
testcase_93	AC	2 ms; 4,348 KB
testcase_94	AC	2 ms; 4,348 KB
testcase_95	AC	2 ms; 4,348 KB
testcase_96	AC	2 ms; 4,348 KB
testcase_97	AC	2 ms; 4,348 KB
testcase_98	AC	2 ms; 4,348 KB
testcase_99	AC	2 ms; 4,348 KB
testcase_100	AC	1 ms; 4,348 KB
testcase_101	AC	1 ms; 4,348 KB
testcase_102	AC	2 ms; 4,348 KB
testcase_103	AC	2 ms; 4,348 KB
testcase_104	AC	1 ms; 4,348 KB
testcase_105	AC	2 ms; 4,348 KB
testcase_106	AC	2 ms; 4,348 KB
testcase_107	AC	2 ms; 4,348 KB
testcase_108	AC	2 ms; 4,348 KB
testcase_109	AC	2 ms; 4,348 KB
testcase_110	AC	2 ms; 4,348 KB
testcase_111	AC	2 ms; 4,348 KB
testcase_112	AC	2 ms; 4,348 KB
testcase_113	AC	2 ms; 4,348 KB
testcase_114	AC	2 ms; 4,348 KB
testcase_115	AC	2 ms; 4,348 KB
testcase_116	AC	1 ms; 4,348 KB
testcase_117	AC	2 ms; 4,348 KB
testcase_118	AC	1 ms; 4,348 KB
testcase_119	AC	2 ms; 4,348 KB
testcase_120	AC	2 ms; 4,348 KB
testcase_121	AC	1 ms; 4,348 KB
testcase_122	AC	3 ms; 4,348 KB
testcase_123	AC	3 ms; 4,348 KB
testcase_124	AC	3 ms; 4,348 KB

コンパイルメッセージ

main.cpp: In function ‘int main()’:
main.cpp:10:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   10 |         scanf("%lld%lld%lld", &a, &b, &c);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

ソースコード

#include <stdio.h>
#include <iostream>
#include <math.h>
#include <assert.h>
#include <iomanip>
using namespace std;
constexpr long double kEps = 1E-13, nEps = 1E-12, kInf = 1E20;
int main() {
	long long int a, b, c;
	scanf("%lld%lld%lld", &a, &b, &c);
	if (a == 0) {
		if (b == 0) {
			if (c == 0) printf("-1\n");
			else printf("0\n");
		}
		else printf("1\n%.20lf\n", (double)((long double)c / (long double) -b));
	}
	else {
		if (a < 0) {
			a = -a;
			b = -b;
			c = -c;
		}
		long double ta(a), tb(b), tc(c), d, sa, sb, l, r, mid;
		d = b * b - 4 * a * c;
		if (b * b - 4 * a * c > 0) {
			if (a >= 100000000) {
				d = sqrtl(d);
				sa = (-tb + d) / ta / 2; 
				sb = (-tb - d) / ta / 2; 
				if (sa < sb) printf("2\n%.20lf\n%.20lf\n", (double) sa, (double) sb);
				else printf("2\n%.20lf\n%.20lf\n", (double) sb, (double) sa);
				return 0;
			}
			cout << 2 << '\n';
			d = sqrtl(d);
			l = -kInf;
			r = -tb / ta / 2 + kEps;
			for (int i = 0; i < 100000; i++) {
				mid = (l + r) / 2;
				if (ta * mid * mid + tb * mid + tc > kEps) l = mid;
				else if(ta * mid * mid + tb * mid + tc < - kEps) r = mid;
			}
			mid = (l + r) / 2;
			cout << setprecision(2000) << mid << '\n';
			sa = a * mid * mid + b * mid + c;
			l = -tb / ta / 2 - kEps;
			r = kInf;
			for (int i = 0; i < 100000; i++) {
				mid = (l + r) / 2;
				if (ta * mid * mid + tb * mid + tc > kEps) r = mid;
				else if(ta * mid * mid + tb * mid + tc < - kEps) l = mid;
			}
			mid = (l + r) / 2;
			cout << setprecision(2000) << mid << '\n';
			sa = a * mid * mid + b * mid + c;
		}
		else if (b * b - 4 * a * c < 0) printf("0\n");
		else printf("1\n%.20lf\n", (double) (-tb / (ta * 2)));
		
	}
	
}