试题D数的分解

 答案：40785

#include
using namespace std;
bool check(int i) {
int x;
while (i) {
x = i % 10;
if (x == 2 || x == 4)
return false;
i /= 10;
}
return true;
}
/*
条件约束：
1.各整数不相等
2.每个整数不含2或4
3.不能有重复的(j=j+1;k=k+1避免不重复)
*/
int main() {
int n = 2019, count = 0, k;
for (int i = 1; i <2000; i++) {
if (check(i)) {
for (int j = i + 1; j <2000; j++) {
if (check(j) && j != i) {
for (int k = j + 1; k <2000; k++) {
if (check(k) && k != i && k != j && i + j + k == 2019) {
count++;
}
}
}
}
}
}
cout < return 0;
}