51nod 1279 扔盘子

#include <bits/stdc++.h>
using namespace std;

const int maxN = 1e5 + 5;

int N, M, S;
int stk[maxN], p;

int main() {
#ifndef ONLINE_JUDGE
    freopen("data.in", "r", stdin);
#endif
    scanf("%d%d", &N, &M);
    p = 0;
    for (int i = 0; i < N; ++i) {
        scanf("%d", &S);
        if (p)
            stk[p] = min(stk[p - 1], S);
        else
            stk[p] = S;
        ++p;
    }
    int ans = 0;
    for (int i = 0; i < M; ++i) {
        scanf("%d", &S);
        while (p && stk[p - 1] < S)
            --p;
        if (!p)
            break;
        ++ans;
        --p;
    }
    printf("%d\n", ans);
    return 0;
}