poj3252.rar_pku 3252_poj32

//#include <algorithm> #include <iostream> using namespace std; static int infoc[64][64]; int max(int a,int b) { return a>b?a:b; } static int counum(int b, int z, unsigned int top) { int ans = 0; if (z > b || top == 0) return 0; if (top >= (1U << b)) { for (int j = max(z, 0); j <= b; j++) ans += infoc[b][j]; return ans; } ans += counum(b - 1, z - 1, top); unsigned int h = 1U << (b - 1); if (top > h && b > z) ans += counum(b - 1, z, top - h); return ans; } static int counumrange(int b, int z, unsigned int start, unsigned int end) { if (start >= end) return 0; return counum(b, z, end) - counum(b, z, start); } int main() { int i; for (i = 0; i < 64; i++) { infoc[i][0] = infoc[i][i] = 1; for (int j = 1; j < i; j++) infoc[i][j] = infoc[i - 1][j - 1] + infoc[i - 1][j]; } unsigned int f, l; int ans = 0; cin >> f >> l; for (i = 1; i <= 31; i++) { unsigned int f1 = max(f, 1U << (i - 1)); ans += counumrange(i, (i + 1) / 2, f1, l + 1); } cout << ans << "\n"; return 0; }