func_code_string: #include<bits/stdc++.h>      using namespace std;   typedef long long ll;   typedef unsigned long long ull;   typedef unsigned int uint;   typedef pair<int, int> pii;      int n, k;   char s[300005];      void solve() {       while (~scanf( %d%d , &n, &k)) {           memset(s, 0, sizeof(s));           s[n + 1] =   0 ;           int top = 0;           s[++top] =  a ;           for (int i = 1; i <= k; ++i) {               char cur =  a  + i - 1;               s[++top] = cur;               for (int j = k; j >= i + 1; --j) {                   char tcur =  a  + j - 1;                   s[++top] = tcur;                   if (j != i + 1)                       s[++top] = cur;               }           }           for (int i = k - 1; i >= 1; --i) {               char cur =  a  + i - 1;               s[++top] = cur;           }   //        puts(s + 1);           int len = top;           int sumlen = len;           while (top <= n) {               for (int i = 2; i <= len; ++i)                   s[++top] = s[i];           }           s[n + 1] =   0 ;           puts(s + 1);       }   }      int main() {       int T = 1;   //    scanf( %d , &T);       for (int i = 1; i <= T; ++i) {   //        printf( Case #%d:  , i);           solve();       }   }   