贪心外加优先队列
#include<stdio.h>
#include<queue>
#include<string.h>
#include<algorithm>
//#include <utility>
using namespace std;
priority_queue <int ,vector<int>,greater<int> > q;
pair <int,int> a[2505];
pair <int,int> b[2505];
int main(){
int c,l;
int i,j,k,ans;
while(scanf("%d%d",&c,&l)!=EOF){
for(i=0;i<c;i++) {
scanf("%d%d",&a[i].first,&a[i].second);
}
for(j=0;j<l;j++) {
scanf("%d%d",&b[j].first,&b[j].second);
}
sort(a,a+c);
sort(b,b+l);
ans=0;
j=0;
for(i=0;i<l;i++){
while(j<c&&a[j].first<=b[i].first) q.push(a[j].second),j++;
while(q.size()&&b[i].second!=0){
k=q.top();
q.pop();
if(k>=b[i].first){
ans++;
b[i].second--;
}
}
}
printf("%d\n",ans);
}
return 0;
}