12 2 2 3
7
/*
Author:ZXPxx
Memory: 1616 KB Time: 202 MS
Language: C++ Result: Accepted
*/
#include <algorithm>
#include <iostream>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <vector>
#include <cmath>
#include <ctime>
#include <queue>
#include <stack>
#include <set>
#include <map>
using namespace std;
typedef long long LL;
const int maxn = 5e5 + 5;
const int inf = 0x3f3f3f3f;
int a[130],n,m,ans,p,cur;
int gcd(int a,int b) {
return !b ? a:gcd(b,a%b);
}
int lcm(int a,int b) {
return a/gcd(a,b)*b;
}
void dfs(int i,int flag,int k)
{
k=lcm(a[i],k);
ans+=n/(k*flag);
for(int j=i+1;j<cur;j++)
dfs(j,-flag,k);
}
int main() {
while(~scanf("%d %d",&n,&m)) {
cur=0;
for(int i=0; i<m; i++) {
scanf("%d",&p);
if(p)
a[cur++]=p;
}
ans=0;n--;
for(int i=0; i < cur; i++) {
dfs(i,1,a[i]);
}
printf("%d\n",ans);
}
return 0;
}/*
Author:ZXPxx
Memory: 1648 KB Time: 998 MS
Language: C++ Result: Accepted
*/
#include <algorithm>
#include <iostream>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <vector>
#include <cmath>
#include <ctime>
#include <queue>
#include <stack>
#include <set>
#include <map>
using namespace std;
typedef long long LL;
const int maxn = 5e5 + 5;
const int inf = 0x3f3f3f3f;
int a[130],m,n,p,cur,ans;
int gcd(int a,int b) {
return !b ? a:gcd(b,a%b);
}
int lcm(int a,int b) {
return a/gcd(a,b)*b;
}
int main() {
while(~scanf("%d %d",&n,&m)) {
n--; cur=0; ans=0;
for(int i=0; i<m; i++) {
scanf("%d",&p);
if(p) a[cur++]=p;
}
for(int i= 1;i < pow(2,cur); i++) {
int cnt=0,flag=0,k=1;
for(int j = 0; j < cur; j++) {
if(i>>j & 1) {
k=lcm(k,a[j]);
if(k>n) {
flag=1;
break;
}
cnt++;
}
}
if(flag) continue;
if(cnt%2)
ans+=n/k;
else
ans-=n/k;
}
printf("%d\n",ans);
}
return 0;
}
版权声明:本文为博主原创文章,未经博主允许不得转载。
HDU 1796 How many integers can you find
原文地址:http://blog.csdn.net/zhang_xueping/article/details/47699787