Структуры С++

Почему оно не работает? вводишь день и выводит занятия на этот день.


#include <iostream>
#include <string.h>
//#include "Func.h"
using namespace std;

int main()
{
struct person {
char monday[150];
char thuersday[150];
char Wednesday[150];
};

person lessons;
char day;
cout << "Vvedit den nedili\n";
cout << "(1) - Monday \n(2) - thuersday \n(3) - Wednesday \n";
cin >> day;

if (day = 1) { strcpy_s(lessons.monday, "\tAlgebra\tGeometria\tInformatika\n"); }
//else
if (day = 2) { strcpy_s(lessons.thuersday, "\tFizika\tHimia\tFizra \n"); }
//else
if (day = 3) { strcpy_s(lessons.Wednesday, "\tGeografia\tRisovanie\n"); }

person *pointer = &lessons;
if (day = 1)
{
cout << "Monday = " << pointer->monday;
}
//else
if (day = 2)
{
cout << "Thuersday = " << pointer->thuersday << endl;
}
//else
if (day = 3)
{
cout << "Wednesday = " << pointer->Wednesday << endl;
}
return 0;
}