第二周---贪心题解（D）

题D Farmer John has a problem: the dirt road from his farm to town has suffered in the recent rainstorms and now contains (1 a[i].x>>a[i].y; } sort(a,a+n,cmp); int sum=0,s=0; for(int i=0;i=a[i].y) continue; s=max(s,a[i].x); while(s