http://acm.hdu.edu.cn/showproblem.php?pid=1859
只要挑出各个坐标最大的就可以了

#include<stdio.h> int main() { int m,n,x1,y1,x2,y2; while(scanf("%ld %ld",&m,&n)&&(m||n)) { x1=x2=m; y1=y2=n; while(scanf("%ld %ld",&m,&n)&&(m||n)) { if(x1<m) x1=m; if(y1<n) y1=n; if(y2>n) y2=n; if(x2>m) x2=m; } printf("%d %d %d %d\n",x2,y2,x1,y1); } return 0; }