1 #include<cstdio> 2 #include<iostream> 3 #include<cstring> 4 #include<cstdlib> 5 #include<algorithm> 6 using namespace std; 7  8 const int maxn = 3000+10; 9 int a[maxn], l[maxn], r[maxn];10 int main() {11     //freopen("test.txt", "r", stdin);12     int n;13     while(scanf("%d", &n)!=EOF) {14         int ans = 0;15         for(int i=0; i<n; i++)16             scanf("%d", &a[i]);17         for(int i=0; i<n; i++) {18             int k = min_element(a+i, a+n)-a; // 找到[a+i, a+n]里面最小元素的下标19             if(i!=k) {20                 swap(a[i], a[k]);21                 l[ans] = i; r[ans] = k; ans++;22             }23         }24         printf("%d\n", ans);25         for(int i=0; i<ans; i++) {26             printf("%d %d\n", l[i], r[i]);27         }28     }29     return 0;30 }