求最长单调递增子序列

Posted 2021-03-18 hqx-curiosity

 

 

//求最长单调递增子序列
#include<stdio.h>
#define MAXN 20
void disp(int a[],int b[],int k){
	int i;
	for(i=k-1;i>0;i--){
		if(b[k] == b[i]+1 && a[i] <= a[k]){
			disp(a,b,i);
			break;
		}
	}
	printf("%d ",a[k]);
}
int maxL(int b[],int n){	//求数组b中最大值下标 k
	int i,k=0;
	int max = b[0];
	for(i = 0;i<n;i++){
		if(max<b[i]){
			max = b[i];
			k = i; 
		} 
	}
	return k;
}
void Maxsubseq(int a[],int b[],int n){
	int i,j,k;
	b[0] = 1;
	for(i=1;i<=n;i++){
		k = 0;
		for(j=0;j<i;j++)
			if(a[j] <= a[i] && k < b[j])
				k = b[j];
		b[i] = k+1;
	}
} 
int main(){
	int a[] = {4,5,1,3,6,7,2,9,8};
	int b[MAXN];
	int n = 8,k;
	Maxsubseq(a,b,n);
	k = maxL(b,n);
	printf("最长单调递增子序列最后元素下标k=%d
",k);
	printf("最长单调递增子序列:");
	disp(a,b,k);
	printf("
");
	return 0;
}