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Diffstat (limited to 'C#')
| -rw-r--r-- | C#/Equations.cs | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/C#/Equations.cs b/C#/Equations.cs new file mode 100644 index 0000000..b7165af --- /dev/null +++ b/C#/Equations.cs @@ -0,0 +1,97 @@ +using System; +using System.Linq; // used only for the input + +namespace Equasions { + class MainClass { + /* Algorithm that solves a system of equation of the type + * | a1 * x + b1 * y = c1 + * | a2 * x + b2 * y = c2 + * via substitution. + * + * At the bottom you can find test cases. + */ + public static void Main(string[] args) { + double[] input = Console.ReadLine().Split().Select(double.Parse).ToArray(); // a1 b1 c1 a2 b2 c2 + + double[] parm = { input[0], input[3], input[1], input[4] }; // a1 a2 b1 b2 + double[] eres = { input[2], input[5] }; // c1 c2 + + double m = 0, n = 0; + string result = null; + + for (int i = 0; i < parm.Length; i++) { + for (int j = 0; j < parm.Length; j++) { + if (parm[i] != 0 || parm[j] != 0) { + continue; + } + + result = (i < 2) ? "n" : "m"; + + if (i == j) { + m = eres[i % 2] / parm[(i + 2) % 4]; + n = (eres[(i + 1) % 2] - parm[3 - i] * m) / parm[(5 - i) % 4]; + } + else if (i + j == 3) { + m = eres[Math.Min(i, j)] / parm[Math.Min(i, j) + 2]; + n = eres[Math.Max(i, j) - 2] / parm[Math.Max(i, j) - 2]; + } + else { + result = "No solution!"; + } + + if ((!double.IsNaN(m) && !double.IsInfinity(m)) || + (!double.IsNaN(n) && !double.IsInfinity(n)) || + result.Length > 1) // if m or n have normal values or if result is "No solution!" + { + j = i = parm.Length; // "breaking" both cycles + } + } + } + + if (result == null) { + m = (parm[0] * eres[1] - parm[1] * eres[0]) / (parm[0] * parm[3] - parm[1] * parm[2]); + n = (eres[0] - parm[2] * m) / parm[0]; + + result = "n"; + } + + if (double.IsInfinity(n) || double.IsInfinity(m)) { + result = "No solution!"; + } + else if (result == "n") { + result = $"X: {(double.IsNaN(n) ? "Any" : n + "")} Y: {(double.IsNaN(m) ? "Any" : m + "")}"; + } + else if (result == "m") { + result = $"X: {(double.IsNaN(m) ? "Any" : m + "")} Y: {(double.IsNaN(n) ? "Any" : n + "")}"; + } + + Console.WriteLine(result); + } + } +} + +/* Example tests (numbers are ordered a1 b1 c1 a2 b2 c2) that: + * + * I. Have a solution (solution is in brackets as (x ; y)): + * 5 -2 1 1 3 7 ( 1; 2) no zeroes + * 0 1 8 1 1 5 (-3; 8) a1 = 0 + * 1 0 8 1 1 5 ( 8;-3) a2 = 0 + * 1 1 8 0 1 5 ( 3; 5) b1 = 0 + * 1 1 8 1 0 5 ( 5; 3) b2 = 0 + * 0 1 3 1 0 9 ( 9; 3) a1 = 0 and b2 = 0 + * 1 0 3 0 1 9 ( 3; 9) a2 = 0 and b1 = 0 + * 0 2 8 0 1 4 (any; 4) a1 = 0 and a2 = 0 + * 2 0 8 1 0 4 ( 4;any) b1 = 0 and b2 = 0 + * 0 0 0 0 0 0 (any;any) all are 0 + * + * II. Don't have a solution: + * 0 0 4 1 1 4 a1 = 0 and b1 = 0 + * 1 1 4 0 0 4 a2 = 0 and b2 = 0 + * 0 0 1 0 0 0 + * + * Problems with this algorithm: + * + * I. Incomplete answers: + * 2 2 2 2 2 2 Answer is (any;any) only when 0 <= x <= 2 and y = 2 - x + */ + |