A.
Examples
Input
120 51840
Output
7
Input
42 42
Output
0
Input
48 72
Output
-1
#include <iostream>
using namespace std;
int main()
{
int m, n;
cin >> m >> n;
int step = 0;
if (n % m != 0)
{
cout << -1 << endl;
return 0;
}
else
{
int k = n / m;
while (k % 2 == 0) {
k /= 2;
step++;
}
while (k % 3 == 0) {
k /= 3;
step++;
}
if (k != 1) {
cout << -1 << endl;
}
else
{
cout << step << endl;
}
}
}
B.
Examples
Input
5
1 0 1 0 1
Output
2
Input
6
0 1 0 1 1 0
Output
2
Input
7
1 0 1 1 1 0 1
Output
3
Input
3
0 0 0
Output
0
#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
int a[200001];
int n;
cin >> n;
for (int i = 0; i < n; ++i) {
cin >> a[i];
}
int s = 0;
int max1 = 0;
if (a[0] == 0) {
for (int i = 1; i < n; i++) {
if (a[i] == 1) {
++s;
max1 = max(s, max1);
continue;
}
max1 = max(s, max1);
s = 0;
}
cout << max1 << endl;
}
if (a[0] == 1) {
if (a[n - 1] == 0) {
for (int i = 0; i < n; i++) {
if (a[i] == 1) {
++s;
max1 = max(s, max1);
continue;
}
max1 = max(s, max1);
s = 0;
}
cout << max1 << endl;
}
else {
int aa = 0;
for (int i = n - 1; a[i] == 1 && i >= 0; i--) {
s++;
aa = i;
}
for (int i = 0; i < aa; i++) {
if (a[i] == 1) {
++s;
max1 = max(s, max1);
continue;
}
max1 = max(s, max1);
s = 0;
}
cout << max1 << endl;
}
}
}