View Compilation Error

0_0_18244382_19039.cpp: In function 'int main()':
0_0_18244382_19039.cpp:19:29: error: expected ';' before ')' token
         for(int i=1;i<=n,i++){
                             ^
0_0_18244382_19039.cpp:22:13: error: expected ';' before 'ans'
             ans+=a;
             ^
0_0_18244382_19039.cpp:27:19: error: 'sum' was not declared in this scope
             if(a<=sum)printf("0");
                   ^