func_code_string: #include <bits/stdc++.h>   using namespace std;   const int P = 1e9 + 7, INF = 0x3f3f3f3f;   long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }   long long qpow(long long a, long long n) {     long long r = 1 % P;     for (a %= P; n; a = a * a % P, n >>= 1)       if (n & 1) r = r * a % P;     return r;   }   long long inv(long long first) {     return first <= 1 ? 1 : inv(P % first) * (P - P / first) % P;   }   inline int rd() {     int first = 0;     char p = getchar();     while (p <  0  || p >  9 ) p = getchar();     while (p >=  0  && p <=  9 ) first = first * 10 + p -  0 , p = getchar();     return first;   }   const int N = 1e6 + 10;   int n, a, b;   struct _ {     long long a, b, c;     void pr() { printf( a=%lld,b=%lld n , a, b); }     bool operator<(const _& rhs) const { return c > rhs.c; }   } e[N];   long long ans;   int vis[N];   int main() {     scanf( %d%d%d , &n, &a, &b);     for (int i = 1; i <= n; ++i) {       scanf( %lld%lld , &e[i].a, &e[i].b);       e[i].c = e[i].a - e[i].b;     }     for (int i = 1; i <= n; ++i) ans += e[i].b;     if (!b) return printf( %lld n , ans), 0;     if (b == 1) {       long long t = 0;       for (int i = 1; i <= n; ++i) t = max(t, (e[i].a << a) - e[i].b);       return printf( %lld n , ans + t), 0;     }     sort(e + 1, e + 1 + n);     for (int i = 1; i <= n; ++i)       if (e[i].a > e[i].b) vis[i] = 1;     int cnt = 0;     for (int i = 1; i <= b; ++i)       if (vis[i]) ans += e[i].a - e[i].b, ++cnt;     long long t = 0;     for (int i = 1; i <= b; ++i) {       if (vis[i])         t = max(t, (e[i].a << a) - e[i].a);       else         t = max(t, (e[i].a << a) - e[i].b);     }     long long ret = ans + t;     t = 0;     for (int i = b + 1; i <= n; ++i) t = max(t, (e[i].a << a) - e[i].b);     if (cnt < b)       ret = max(ret, ans + t);     else       ret = max(ret, ans + t - e[b].a + e[b].b);     printf( %lld n , ret);   }   