Codeforces Round #584 B

#include <bits/stdc++.h>
using namespace std;
 bool status[101][2001];
    int n,a[101],b[101];
    char s[101];
int main()
{
 
    cin>>n;
    cin>>s;
    for (int i=1;i<=n;i++)
        cin>>a[i]>>b[i];
 
for (int i=1;i<=n;i++)
{
    for (int t=0;t<=2001;t++)
    {
        if (t<b[i]) {
            if (s[i-1]==‘1‘) status[i][t]=1; else status[i][t]=0;
        }
        else
        {//toggle以后
            if ((t-b[i]+1) % (2*a[i])>a[i] || (t-b[i]+1) % (2*a[i])==0) {
                if (s[i-1]==‘1‘) status[i][t]=1; else status[i][t]=0;
            }
            else {
                if (s[i-1]==‘1‘) status[i][t]=0; else status[i][t]=1;
            }
        }
    }
}
int ans=0,temp=0;
 
for (int t=0;t<=2001;t++)
{
    temp=0;
    for (int i=1;i<=n;i++)
    {
        if (status[i][t]==1) temp++;
    }
    if (temp>ans) ans=temp;
}
 
cout<<ans;
 
 
return 0;
}