Language: C++

#include <bits/stdc++.h>
#include <math.h>
using namespace std;

int main() {
  float N;
  cin >> N;
  float A, B, C, D, E, F, G, H, I, J, K;
  float AAA, AA, BBB, BB
  int P, Q, R, S, T, U, V, W, X, Y, Z;
  
  AAA = fmodf(N, 26*26*26*26);
  AA = fmodf(AAA, 26*26*26);
  A = fmodf(AA, 26*26*26);
  P = A-1;
  N = N-A*26*26*26*26*26*26*26*26*26*26;
  B = fmodf(N, 26*26*26*26*26*26*26*26*26);
  Q = B-1;
  N = N-B*26*26*26*26*26*26*26*26*26;
  C = fmodf(N, 26*26*26*26*26*26*26*26);
  R = C-1;
  N = N-C*26*26*26*26*26*26*26*26;
  D = fmodf(N, 26*26*26*26*26*26*26);
  S = D-1;
  N = N-D*26*26*26*26*26*26*26;
  E = fmodf(N, 26*26*26*26*26*26);
  T = E-1;
  N = N-E*26*26*26*26*26*26;
  F = fmodf(N, 26*26*26*26*26);
  U = F-1;
  N = N-F*26*26*26*26*26;
  G = fmodf(N, 26*26*26*26);
  V = G-1;
  N = N-G*26*26*26*26;
  H = fmodf(N, 26*26*26);
  W = H-1;
  N = N-H*26*26*26;
  I = fmodf(N, 26*26);
  X = I-1;
  N = N-I*26*26;
  J = fmodf(N, 26);
  Y = J-1;
  N = N-J*26;
  K = N;
  Z = K-1;
  
  vector<int> vec(11);
  vec.at(0) = P;
  vec.at(1) = Q;
  vec.at(2) = R;
  vec.at(3) = S;
  vec.at(4) = T;
  vec.at(5) = U;
  vec.at(6) = V;
  vec.at(7) = W;
  vec.at(8) = X;
  vec.at(9) = Y;
  vec.at(10) = Z;
  
  string Ans; 
  
  for (M = 0; M < 11; M++) {
    if (vec.at(M) == 0)
      Ans += "a";
    if (vec.at(M) == 1)
      Ans += "b";
    if (vec.at(M) == 2)
      Ans += "c";
    if (vec.at(M) == 3)
      Ans += "d";
    if (vec.at(M) == 4)
      Ans += "e";
    if (vec.at(M) == 5)
      Ans += "f";
    if (vec.at(M) == 6)
      Ans += "g";
    if (vec.at(M) == 7)
      Ans += "h";
    if (vec.at(M) == 8)
      Ans += "i";
    if (vec.at(M) == 9)
      Ans += "j";
    if (vec.at(M) == 10)
      Ans += "k";
    if (vec.at(M) == 11)
      Ans += "l";
    if (vec.at(M) == 12)
      Ans += "m";
    if (vec.at(M) == 13)
      Ans += "n";
    if (vec.at(M) == 14)
      Ans += "o";
    if (vec.at(M) == 15)
      Ans += "p";
    if (vec.at(M) == 16)
      Ans += "q";
    if (vec.at(M) == 17)
      Ans += "r";
    if (vec.at(M) == 18)
      Ans += "s";
    if (vec.at(M) == 19)
      Ans += "t";
    if (vec.at(M) == 20)
      Ans += "u";
    if (vec.at(M) == 21)
      Ans += "v";
    if (vec.at(M) == 22)
      Ans += "w";
    if (vec.at(M) == 23)
      Ans += "x";
    if (vec.at(M) == 24)
      Ans += "y";
    if (vec.at(M) == 25)
      Ans += "z";
  }
  cout << Ans << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:10:3: error: expected initializer before 'int'
   10 |   int P, Q, R, S, T, U, V, W, X, Y, Z;
      |   ^~~
a.cc:15:3: error: 'P' was not declared in this scope
   15 |   P = A-1;
      |   ^
a.cc:17:33: warning: integer overflow in expression of type 'int' results in '-558124416' [-Woverflow]
   17 |   B = fmodf(N, 26*26*26*26*26*26*26*26*26);
      |                ~~~~~~~~~~~~~~~~~^~~
a.cc:18:3: error: 'Q' was not declared in this scope
   18 |   Q = B-1;
      |   ^
a.cc:20:33: warning: integer overflow in expression of type 'int' results in '-558124416' [-Woverflow]
   20 |   C = fmodf(N, 26*26*26*26*26*26*26*26);
      |                ~~~~~~~~~~~~~~~~~^~~
a.cc:21:3: error: 'R' was not declared in this scope
   21 |   R = C-1;
      |   ^
a.cc:23:33: warning: integer overflow in expression of type 'int' results in '-558124416' [-Woverflow]
   23 |   D = fmodf(N, 26*26*26*26*26*26*26);
      |                ~~~~~~~~~~~~~~~~~^~~
a.cc:24:3: error: 'S' was not declared in this scope
   24 |   S = D-1;
      |   ^
a.cc:27:3: error: 'T' was not declared in this scope
   27 |   T = E-1;
      |   ^
a.cc:30:3: error: 'U' was not declared in this scope
   30 |   U = F-1;
      |   ^
a.cc:33:3: error: 'V' was not declared in this scope
   33 |   V = G-1;
      |   ^
a.cc:36:3: error: 'W' was not declared in this scope
   36 |   W = H-1;
      |   ^
a.cc:39:3: error: 'X' was not declared in this scope
   39 |   X = I-1;
      |   ^
a.cc:42:3: error: 'Y' was not declared in this scope
   42 |   Y = J-1;
      |   ^
a.cc:45:3: error: 'Z' was not declared in this scope
   45 |   Z = K-1;
      |   ^
a.cc:62:8: error: 'M' was not declared in this scope
   62 |   for (M = 0; M < 11; M++) {
      |        ^