POJ 2743:字符串判等

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main()
{

    char a[105],b[105],a_1[105],b_1[105];
    int i,j,loop,num;int lu;
    scanf("%d",&num);getchar();
    while(num--)
    {
        gets(a);
        gets(b);getchar();
        if(a[0]=='\n' && b[0]=='\n')
        {
            printf("YES\n");continue;
        }
        j=0;loop=0;
        for(i=0;i<strlen(a);i++)
        {
            if(a[i]==' ')
            {
              continue;
            }
            if(a[i]>='a' && a[i] <= 'z')
                a[i]-=32;
            a_1[j]=a[i];
            j++;
        }
        a_1[j]='\0';
         j=0;
        for(i=0;i<strlen(b);i++)
        {
            if(b[i]==' ')
            {
              continue;
            }
            if(b[i]>='a' && b[i] <= 'z')
                b[i]-=32;
            b_1[j]=b[i];
            j++;
        }
        b_1[j]='\0';

        if(strlen(a_1) == strlen(b_1))
        {
            lu=strlen(a_1);
            for(i=0;i<strlen(a_1);i++)
            {
                if(a_1[i]!=b_1[i])
                    break;
            }
            if( i!=lu)
                loop=1;
        }
        else loop=1;
        if(loop)
            printf("NO\n");
        else
            printf("YES\n");

    }
    return 0;
}