View Compilation Error

0_0_23988140_23768.cpp: In function 'int main()':
0_0_23988140_23768.cpp:9:4: error: 'sun' was not declared in this scope
    sun=0;
    ^
0_0_23988140_23768.cpp:10:9: error: 'a' was not declared in this scope
    cin>>a;
         ^
0_0_23988140_23768.cpp:11:8: error: 'j' was not declared in this scope
    for(j=1;j<=a;j++)
        ^