В переменной day определяется номер последнего элемента массива Dat, который равен первому элементу ⇒ значение переменной day после выполнения цикла = 2
Математическая модель - это фактически просто формула.
![\displaystyle A=\left(\begin{array}{cccc}a_{1,1}&a_{1,2}&...&a_{1,m}\\a_{2,1}&a_{2,2}&...&a_{2,m}\\&&...&\\a_{n,1}&a_{n,2}&...&a_{n,m}\end{array}\right); \\ \\B=\left(\begin{array}{cccc}b_{1,1}&b_{1,2}&...&b_{1,l}\\b_{2,1}&b_{2,2}&...&b_{2,l}\\&&...&\\b_{m,1}&b_{m,2}&...&b_{m,l}\end{array}\right); \\ \\C=\left(\begin{array}{cccc}c_{1,1}&c_{1,2}&...&c_{1,l}\\c_{2,1}&c_{2,2}&...&c_{2,l}\\&&...&\\c_{n,1}&c_{n,2}&...&c_{n,l}\end{array}\right); \\ \\C_{i,j}=\sum_{k=1}^mA_{i,k}\times B_{k,j}](https://tex.z-dn.net/?f=%5Cdisplaystyle+A%3D%5Cleft%28%5Cbegin%7Barray%7D%7Bcccc%7Da_%7B1%2C1%7D%26a_%7B1%2C2%7D%26...%26a_%7B1%2Cm%7D%5C%5Ca_%7B2%2C1%7D%26a_%7B2%2C2%7D%26...%26a_%7B2%2Cm%7D%5C%5C%26%26...%26%5C%5Ca_%7Bn%2C1%7D%26a_%7Bn%2C2%7D%26...%26a_%7Bn%2Cm%7D%5Cend%7Barray%7D%5Cright%29%3B+%5C%5C+%5C%5CB%3D%5Cleft%28%5Cbegin%7Barray%7D%7Bcccc%7Db_%7B1%2C1%7D%26b_%7B1%2C2%7D%26...%26b_%7B1%2Cl%7D%5C%5Cb_%7B2%2C1%7D%26b_%7B2%2C2%7D%26...%26b_%7B2%2Cl%7D%5C%5C%26%26...%26%5C%5Cb_%7Bm%2C1%7D%26b_%7Bm%2C2%7D%26...%26b_%7Bm%2Cl%7D%5Cend%7Barray%7D%5Cright%29%3B+%5C%5C+%5C%5CC%3D%5Cleft%28%5Cbegin%7Barray%7D%7Bcccc%7Dc_%7B1%2C1%7D%26c_%7B1%2C2%7D%26...%26c_%7B1%2Cl%7D%5C%5Cc_%7B2%2C1%7D%26c_%7B2%2C2%7D%26...%26c_%7B2%2Cl%7D%5C%5C%26%26...%26%5C%5Cc_%7Bn%2C1%7D%26c_%7Bn%2C2%7D%26...%26c_%7Bn%2Cl%7D%5Cend%7Barray%7D%5Cright%29%3B+%5C%5C+%5C%5CC_%7Bi%2Cj%7D%3D%5Csum_%7Bk%3D1%7D%5EmA_%7Bi%2Ck%7D%5Ctimes+B_%7Bk%2Cj%7D)
1) Мода, конечно, Тихий океан (47 наименований).
2) Средняя цена:
fcp = (26*26 + 33* 35+ 47*28 +15*41) / (26+33+47+15) ≈ 31 руб
program raf105;
var
a,b,c,k: real;
begin
write('a = ');
readln(a);
write('b = ');
readln(b);
write('c = ');
readln(c);
if a*b*c <> 0 then k:= sqrt(a*b*c)
else k:= (a+b+c) / 2;
writeln('k = ',k);
end.
<h3>PascalABC</h3>