foo.cc: In function 'int main()':
foo.cc:12:3: error: 'z' was not declared in this scope
   z=t;
   ^
foo.cc:15:11: error: expected ';' before 'z'
    s+=a[j]z;
           ^
foo.cc:5:24: warning: unused variable 'k' [-Wunused-variable]
     int n,m,i,a[100],j,k=1,s,t;
                        ^
foo.cc:20:1: error: expected '}' at end of input
 }
 ^

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