1 #include <cstdio> 2 #include <cstring> 3 #include <algorithm> 4 #define maxn 200000 5 #define ll __int64 6 using namespace std; 7  8 ll dp[maxn][12]; 9 int n;10 ll max1(ll a,ll b,ll c)11 {12     return (a>b?a:b)>c?(a>b?a:b):c;13 }14 15 int main()16 {17     while(scanf("%d",&n)!=EOF)18     {19         memset(dp,0,sizeof(dp));20         if(n==0) break;21         int max2=-1;22         int x,t;23         for(int i=1; i<=n; i++)24         {25             scanf("%d%d",&x,&t);26             dp[t][x+1]++;27             max2=max(max2,t);28         }29         for(int i=max2; i>=0; i--)30         {31             for(int j=1; j<=11; j++)32             {33                 dp[i][j]+=max1(dp[i+1][j-1],dp[i+1][j],dp[i+1][j+1]);34             }35         }36         printf("%I64d\n",dp[0][6]);37     }38     return 0;39 }