View Compilation Error

0_0_13827331_8718.cpp: In function 'int main()':
0_0_13827331_8718.cpp:40:13: error: redeclaration of 'int len'
         int len = solve();
             ^
0_0_13827331_8718.cpp:14:13: note: 'int len' previously declared here
         int len = 1;
             ^
0_0_13827331_8718.cpp:40:25: error: 'solve' was not declared in this scope
         int len = solve();
                         ^