func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, m, ans = 1e9;   int a[100005];   inline int read() {     int x = 0, f = 1;     char ch = getchar();     for (; ch <  0  || ch >  9 ; ch = getchar())       if (ch ==  - ) f = -1;     for (; ch >=  0  && ch <=  9 ; ch = getchar()) x = x * 10 + ch -  0 ;     return x * f;   }   inline void print(int x) {     if (x >= 10) print(x / 10);     putchar(x % 10 +  0 );   }   int main() {     n = read(), m = read();     for (int i = 1, l, r; i <= m; i++)       l = read(), r = read(), ans = min(ans, r - l + 1);     for (int i = 1; i <= ans; i++) a[i] = i - 1;     for (int i = ans + 1; i <= n; i++) a[i] = a[i - ans];     print(ans);     puts(  );     for (int i = 1; i <= n; i++) print(a[i]), putchar(   );     puts(  );     return 0;   }   