题解

通过结构体、数组和循环嵌套组合，完成程序；

#include <iostream>
using namespace std;

struct node {
    int start;
    int end;
} a[10005];

int main() {
    int l, m, sum = 0;
    cin >> l >> m;
    int t[l + 5];
    for (int i = 0; i <= l; i++) {
        t[i] = 1;
    }
    for (int i = 0; i < m; i++) {
        cin >> a[i].start >> a[i].end;
    }
    for (int i = 0; i < m; i++) {
        for (int j = a[i].start; j <= a[i].end; j++) {
            t[j] = 0;
        }
    }
    for (int i = 0; i <= l; i++) {
        sum += t[i];
    }
    cout << sum;
    return 0;
}