View Compilation Error

0_0_22048188_19072.cpp:60:11: error: 'N' was not declared in this scope
 char str1[N];
           ^
0_0_22048188_19072.cpp:61:7: error: 'N' was not declared in this scope
 int q[N];
       ^
0_0_22048188_19072.cpp:62:8: error: 'N' was not declared in this scope
 int sa[N],k; //sa[i]表示排在第i位的后缀的首字母下标;
        ^