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24 lines
323 B
C++
24 lines
323 B
C++
#include <bits/stdc++.h>
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using namespace std;
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int l, r, ans;
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int cnt2(int x) {
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int res = 0;
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while (x) {
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res += x % 10 == 2;
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x /= 10;
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}
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return res;
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}
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int main() {
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cin >> l >> r;
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for (int i = l; i <= r; i++) {
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ans += cnt2(i);
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}
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cout << ans << endl;
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return 0;
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}
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