hdu 2491 Priest John's Busiest Day（动态规划之贪心）
http://acm.hdu.edu.cn/showproblem.php?pid=2491
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1 #include<stdio.h> 2 #include<stdlib.h> 3 #define N 100008 4 struct cere 5 { 6 int x,y; 7 int mid,end; 8 }a[N]; 9 int cmp(const void *a,const void *b) 10 { 11 struct cere *c,*d; 12 c=(struct cere *)a; 13 d=(struct cere *)b; 14 if(c->y!=d->y) 15 return c->y-d->y; 16 else 17 return c->x-d->x; 18 } 19 int main() 20 { 21 int n,i,x,y; 22 while(scanf("%d",&n),n!=0) 23 { 24 for(i=0;i<n;i++) 25 { 26 scanf("%d%d",&x,&y); 27 a[i].x=x; 28 a[i].mid=(y-x)/2+1; 29 a[i].y=x+a[i].mid; 30 a[i].end=y; 31 } 32 qsort(a,n,sizeof(a[0]),cmp); 33 int flag=0,time; 34 time=0; 35 for(i=0;i<n;i++) 36 { 37 if(time>(a[i].end-a[i].mid)) 38 break; 39 if(time>=a[i].x) 40 time+=a[i].mid; 41 else 42 time=a[i].y; 43 } 44 if(i>=n) 45 printf("YES\n"); 46 else 47 printf("NO\n"); 48 } 49 return 0; 50 } 51 52 53 54
