Main.cc: In function 'int main()':
Main.cc:8:21: error: 'strlen' was not declared in this scope
int len=strlen(a),y=1;
^
Main.cc:11:20: error: 'y' was not declared in this scope
if(a[i]==b[y])
^
Main.cc:16:8: error: 'y' was not declared in this scope
if(y==5)
^