View Compilation Error

0_0_35840538_32594.cpp: In function 'int main()':
0_0_35840538_32594.cpp:43:8: error: redeclaration of 'int len'
    int len=n;
        ^
0_0_35840538_32594.cpp:28:8: note: 'int len' previously declared here
    int len=n;
        ^
0_0_35840538_32594.cpp:78:8: error: redeclaration of 'int len'
    int len=n;
        ^
0_0_35840538_32594.cpp:62:8: note: 'int len' previously declared here
    int len=n;
        ^