#include <bits/stdc++.h> using namespace std; using lli = int_fast64_t; using ulli = uint_fast64_t; #define debug(x) cerr << #x << " : " << x << endl #define debugv(x) cerr << #x << " : {";for(auto value_of_x:x){ cerr << value_of_x << ", ";}cerr << endl #define debugst(x) auto xt = x;cerr << #x << " : {";for(int i=0;i<x.size();i++){ cerr << xt.top() << ", ";xt.pop();}cerr << endl #define debugvp(x) cerr << #x << " : {";for(auto value_of_x:x){ cerr << value_of_x.first << " : " << value_of_x.second << ", ";}cerr << endl template<typename T> T ncr(T left, T right) { right = min(left - right, right); T ans = 1; for (T i = 1; i <= right; i++) { ans = ans * (left - right + i) / i; } return ans; } const lli MOD = 1000000007; const lli LIMIT = 1000000000000000000 * 5; const int tenfive = 100000; int main() { int L, R, M; cin >> L >> R >> M; int c = R - L + 1; cout << min(c,M) << endl; return 0; }