请调试她

[pan2008]

请调试她
void F_007()
{
int i,j,upp,low,dig,spa,oth;
char text[3][80];

upp=low=dig=spa=oth=0;

for(i=0;i<3;i++)
{
printf("\nPlease input line %d:",i+1);

gets(text[i]);

for(j=0;j<80&&text[i][j]!='\0';j++)
{
if(text[i][j]>='A'&&text[i][j]<='Z')
upp++;
else if(text[i][j]>='a'&&text[i][j]<='z')
low++;
else if(text[i][j]>='0'&&text[i][j]<='9')
dig++;
else if(text[i][j]=='') //err here
spa++;
else
oth++;
}
}

}

///////////////////////
error C2137: empty character constant