View Compilation Error

0_0_27566560_1680.cpp: In function 'long long int sol()':
0_0_27566560_1680.cpp:77:15: error: 'n' was not declared in this scope
   for(int i = n-1; i >=0; i--) {
               ^
0_0_27566560_1680.cpp:78:23: error: 'm' was not declared in this scope
    for(int k = 1; k <=m; ++k) {
                       ^
0_0_27566560_1680.cpp: In function 'int main()':
0_0_27566560_1680.cpp:101:16: error: 'n' was not declared in this scope
    scanf("%d",&n);
                ^
0_0_27566560_1680.cpp:109:4: error: 'm' was not declared in this scope
    m=(int)sqrt(n*2)+1;
    ^