poj 1083 求n条线段覆盖的最大相交次数

#include<cstdio>#include<cstring>#define MAX(x,y) ((x)>(y)?(x):(y))int vis[200100];int dp[200100];int main(){int T;scanf("%d",&T);while(T--){int n,tot=-1;memset(vis,0,sizeof(vis));memset(dp,0,sizeof(dp));scanf("%d",&n);for(int i=1;i<=n;i++){int a,b;scanf("%d%d",&a,&b);if(b<a){int tem=b;    b=a;    a=tem;} a=(a+1)/2;b=(b+1)/2+1;vis[a]++;vis[b]--; tot=MAX(tot,b); }  int res=-1;for(int i=1;i<=tot;i++){dp[i]=dp[i-1]+vis[i];res=MAX(res,dp[i]);}printf("%d\n",res*10);}return 0; }