View Compilation Error

0_0_13941302_26787.cpp: In function 'void dp(int)':
0_0_13941302_26787.cpp:28:24: error: 'f' was not declared in this scope
             if ( max > f[j] ) {
                        ^
0_0_13941302_26787.cpp:35:9: error: 'f' was not declared in this scope
         f[a[i]] = max + 1;
         ^
0_0_13941302_26787.cpp:35:11: error: 'a' was not declared in this scope
         f[a[i]] = max + 1;
           ^
0_0_13941302_26787.cpp:41:20: error: 'f' was not declared in this scope
         if ( max > f[j] ) {
                    ^
0_0_13941302_26787.cpp: In function 'int main()':
0_0_13941302_26787.cpp:59:13: error: 'a' was not declared in this scope
             a[i] = str[i] - 'a' + 1;
             ^