foo.cc: In function 'void stringZip(const char*, long int, char*)':
foo.cc:9:6: warning: unused variable 'j' [-Wunused-variable]
 char j,m;
      ^
foo.cc:9:8: warning: unused variable 'm' [-Wunused-variable]
 char j,m;
        ^
foo.cc: In function 'int main()':
foo.cc:47:5: error: 'solve' was not declared in this scope
     solve(s,ans);
     ^~~~~
foo.cc:46:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%s",s);           //s为要处理的加密字符串，答案储存在ans里
     ~~~~~^~~~~~~~

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