A61486 | 2019年信奥赛csp-j 初赛阅读程序2：#include<bits/stdc++.h>

2019年信奥赛csp-j 初赛阅读程序2：

#include<bits/stdc++.h>
using namespace std;
int n, m;
int a[100], b[100];
int main() {
    scanf("%d%d", &n, &m);
    for (int i = 1; i <= n; ++i)
        a[i] = b[i] = 0;
    for (int i = 1; i <= m; ++i) {
        int x, y;
        scanf("%d%d", &x, &y);
        if (a[x] < y && b[y] < x) {
            if (a[x] > 0)
                b[a[x]] = 0;
            if (b[y] > 0)
                a[b[y]] = 0;
            a[x] = y;
            b[y] = x;
        }
    }
    int ans = 0;
    for (int i = 1; i <= n; ++i) {
        if (a[i] == 0)
            ++ans;
        if (b[i] == 0)
            ++ans;
    }
    printf("%d", ans);
    return 0;
}
//假设输入的n和m都是正整数,x和y都是在[1,n]的范围内的整数,完成判断题