Submission #509755

#	Time	Username	Problem	Language	Result	Execution time	Memory
509755		tht2005	Guess the number (BOI20_guess)	C++14	0 / 100	0 ms	200 KiB

Guess

#include <bits/stdc++.h>

using namespace std;

int rd() {
    bool neg = 0; char c = getchar(); for(; c < '0' || c > '9'; c = getchar()) if(c == '-') neg = !neg;
    int n = 0; while('0' <= c && c <= '9') n = (n << 3) + (n << 1) + c - '0', c = getchar();
    return neg ? -n : n;
}
void wr(int n) {
    static char o[11];
    if(n < 0) putchar('-'), n = -n;
    int i = 0; do o[i++] = n % 10 + '0'; while(n /= 10);
    while(i--) putchar(o[i]);
}

int main() {
    int l = 1, r = rd();
    while(l <= r) {
        int m = (l + r) >> 1;
      	printf("? %d\n", m);
        fflush(stdout);
        int x = rd();
        if(!x) {
          	printf("= %d\n", m);
            fflush(stdout);
            break;
        }
        if(x < 0) r = m - 1;
        else l = m + 1;
    }
    return 0;
}

• Subtask 1: 0 / 29
• Subtask 2: 0 / 71