def fun(d,ubound):
c = int(.1*ubound)
if(d!=0 and ubound%10>=d):
c+=1
return c
n,m = map(int,input().split(' '))
count = 0
for a in range(0,10):
b = 10-a
if(b==10):b=0
c1= fun(a,n)
c2= fun(b,m)
count += c1*c2
if(a<=5):
b2=5-a
else:
b2=15-a
c3=fun(b2,m)
count+= c1*c3
print(count)#include<bits/stdc++.h>
using namespace std;
#define int long long
const int MOD = 1e9 + 7;
const int INF = LLONG_MAX >> 1;
void solve(int n,int m)
{
int freq1[5]={0,0,0,0,0};
int freq2[5]={0,0,0,0,0};
for(int i=1;i<=n;i++)
{
int rem=i%5;
freq1[rem]++;
}
for(int i=1;i<=m;i++)
{
int rem=i%5;
freq2[rem]++;
}
int ans=freq1[0]*freq2[0]+freq1[1]*freq2[4]+freq1[2]*freq2[3]+freq1[3]*freq2[2]+freq1[4]*freq2[1];
cout<<ans<<endl;
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n,m;
cin>>n>>m;
solve(n,m);
}1711D - Rain | 534A - Exam |
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