时区间时间的转换

//时区间时间的转换
#include<stdio.h>
#include<string.h>

int difference(char *zone1,char *zone2)
{
	char zone[32][10]={"UTC","GMT","BST","IST","WET","WEST","CET","CEST","EET","EEST","MSK","MSD","AST","ADT","NST","NDT","EST","EDT","CST","CDT","MST","MDT","PST","PDT","HST","AKST","AKDT","AEST","AEDT","ACST","ACDT","AWST"};
	float time[32]={0,0,1,1,0,1,1,2,2,3,3,4,-4,-3,-3.5,-2.5,-5,-4,-6,-5,-7,-6,-8,-7,-10,-9,-8,10,11,9.5,10.5,8};
	int i,j;
	for(i=0;strcmp(zone[i],zone1);i++);
	for(j=0;strcmp(zone[j],zone2);j++);
	return (int)((time[i]-time[j])*60);
}
int main()
{
	int nCases,i;
	scanf("%d",&nCases);
	for(i=0;i<nCases;i++)
	{
		int hours,minute;
		char time[9];
		scanf("%s",time);		
		switch(time[0])
		{
			case 'n':hours=12;
					 minute=0;
					 break;
			case 'm':hours=0;
					 minute=0;
					 break;
			default:sscanf(time,"%d:%d",&hours,&minute);
					hours=hours%12;
					scanf("%s",time);
					if(time[0]=='p') hours+=12;
		}
		char timezone1[5],timezone2[5];
		scanf("%s%s",timezone1,timezone2);
		int newTime;
		newTime=hours*60+minute+difference(timezone2,timezone1);
		if(newTime<0) newTime+=1440;
		newTime%=1440;
		switch(newTime)
		{
			case 0:printf("midnight
");
			break;
			case 720:printf("noon
");
			break;
			default:
				hours=newTime/60;
				minute=newTime%60;
				if(hours==0)
					printf("12:%02d a.m.
",minute);
				else if(hours<12)
					printf("%d:%02d a.m.
",hours,minute);
				else if(hours==12)
					printf("12:%02d p.m.
",minute);
				else
					printf("%d:%02d p.m.
",hours%12,minute);
		}
	}
	return 0;
}