#include #define EM 1000000 using namespace std; using LL = long long; using P = pair; LL LINF = 1e18; int INF = 1e9; LL mod = 1e9+7; using vint = vector; using vLL = vector; using vvint = vector>; using vvLL = vector>; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } int main(){ int N, K; cin >> N >> K; vector x(K), y(K), end(N); for(int i = 0;i < K;i++){ int xi, yi; cin >> xi >> yi; x[i] = xi-1, y[i] = yi-1; } for(int i = 0;i < N;i++){ cin >> end[i]; end[i]--; } vector srt(N); iota(srt.begin(), srt.end(), 0); for(int i = 0;i < K;i++){ int id = x[i]; srt[id] ^= srt[id+1] ^= srt[id] ^= srt[id+1]; } vector> ans; for(int i = 0;i < N;i++){ for(int j=0;jend[srt[j+1]]) { ans.push_back(make_pair(j,j+1)); srt[j]^=srt[j+1]^=srt[j]^=srt[j+1]; } } } cout << ans.size() << endl; for(int i = 0;i < ans.size();i++) cout << ((ans[i].first)+1) << " " << ((ans[i].second)+1) << endl; }