View Compilation Error

0_0_32312258_30997.cpp: In function 'int main()':
0_0_32312258_30997.cpp:17:8: error: 'i' was not declared in this scope
    for(i=0;a[i]!=strlen(a);i++)
        ^
0_0_32312258_30997.cpp:19:19: error: 's' was not declared in this scope
     if(a[i]>='0'&&s[i]<='9')r=1;
                   ^
0_0_32312258_30997.cpp:20:19: error: 's' was not declared in this scope
     if(a[i]>='a'&&s[i]<='z')p=1;
                   ^
0_0_32312258_30997.cpp:21:19: error: 's' was not declared in this scope
     if(a[i]>='A'&&s[i]<='Z')k=1;
                   ^