View Compilation Error

0_0_22089324_15355.cpp: In function 'int main()':
0_0_22089324_15355.cpp:19:9: error: 'ans' was not declared in this scope
         ans = -INF:
         ^
0_0_22089324_15355.cpp:19:16: error: 'INF' was not declared in this scope
         ans = -INF:
                ^
0_0_22089324_15355.cpp:20:24: error: 'i' was not declared in this scope
         for(int i = n; i >= 1; --i){
                        ^