NHOI小学组T4：好数题解

smsy_sxq · 2024-01-21 09:59:07 · 个人记录

include<bits/stdc++.h>

using namespace std;

struct node

{

int jsh,osh;

int jsh2,osh2;

}a[200005];

int n,b[200005],ans=0;

int main(){

cin>>n;

for(int i=1;i<=n;i++)

    cin>>b[i];

for(int i=2;i<=n;i++)

{

    a[i].jsh=a[i-1].jsh;

    a[i].osh=a[i-1].osh;

    if((i-1)%2==0) a[i].osh+=b[i-1];

    else a[i].jsh+=b[i-1];

}

for(int i=n-1;i>=1;i--)

{

    a[i].jsh2=a[i+1].jsh2;

    a[i].osh2=a[i+1].osh2;

    if((i+1)%2==0) a[i].osh2+=b[i+1];

    else a[i].jsh2+=b[i+1];

}

//for(int i=1;i<=n;i++)

//  cout<<a[i].jsh2<<" "<<a[i].osh2<<endl;

for(int i=1;i<=n;i++)

    if(a[i].jsh+a[i].osh2==a[i].osh+a[i].jsh2) ans++;

cout<<ans;

return 0;

}