AOJ/堆与动态规划习题集

ALDS1_9_A-CompleteBinaryTree.

Codes:

//#define LOCAL

include

int parent(int i) { return i/2; }
int left(int i) { return i2; }
int right(int i) { return i2+1; }

int main()
{
#ifdef LOCAL
freopen("E:\Temp\input.txt", "r", stdin);
freopen("E:\Temp\output.txt", "w", stdout);
#endif

int i, n, A[300];
scanf("%d", &n);
for(i=1; i<=n; ++i) scanf("%d", &A[i]);

for(i=1; i<=n; ++i) {
printf("node %d: key = %d, ", i, A[i]);
if(parent(i) >= 1) printf("parent key = %d, ", A[i/2]);
if(left(i) <= n) printf("left key = %d, ", A[i2]);
if(right(i) <= n) printf("right key = %d, ", A[i2+1]);
printf("\n");
}

return 0;
}

ALDS1_9_B-MaximumHeap.

Codes:

//#define LOCAL

include

int i, n, A[500010];

void swap(int &a, int &b) {
int t = a;
a = b; b = t;
}

void maxHeapify(int a) {
int l = a2, r = a2+1, maxn;
if(l<=n && A[l]>A[a]) maxn = l;
else maxn = a;
if(r<=n && A[r]>A[maxn]) maxn = r;
if(maxn != a) {
swap(A[maxn], A[a]);
maxHeapify(maxn);
}
}

int main()
{
#ifdef LOCAL
freopen("E:\Temp\input.txt", "r", stdin);
freopen("E:\Temp\output.txt", "w", stdout);
#endif

scanf("%d", &n);
for(i=1; i<=n; ++i) scanf("%d", &A[i]);

for(i=n/2; i>=1; --i) maxHeapify(i);
for(i=1; i<=n; ++i) printf(" %d", A[i]);
printf("\n");

return 0;
}

ALDS1_9_C-PriorityQueue.

Codes:

//#define LOCAL

include

define M 2000000

define I (1<<30)

int i, n, A[M];

void swap(int &a, int &b) {
int t = a;
a = b; b = t;
}

void maxHeapify(int a) {
int l = a2, r = a2+1, maxn;
if(l<=n && A[l]>A[a]) maxn = l;
else maxn = a;
if(r<=n && A[r]>A[maxn]) maxn = r;
if(maxn != a) {
swap(A[maxn], A[a]);
maxHeapify(maxn);
}
}

int extract() {
int maxv;
if(n < 1) return -I;
maxv = A[1]; A[1] = A[n--];
maxHeapify(1);
return maxv;
}

void increaseKey(int i, int key) {
if(key < A[i]) return;
A[i] = key;
while(i>1 && A[i/2]<A[i]) {
swap(A[i], A[i/2]);
i /= 2;
}
}

void insert(int key) {
++n;
A[n] = -I;
increaseKey(n, key);
}

int main()
{
#ifdef LOCAL
freopen("E:\Temp\input.txt", "r", stdin);
freopen("E:\Temp\output.txt", "w", stdout);
#endif

int key;
char com[10];

while(1) {
scanf("%s", com);
if(com[0]'e' && com[1]'n') break;
if(com[0] == 'i') {
scanf("%d", &key);
insert(key);
} else printf("%d\n", extract());
}

return 0;
}

ALDS1_10_A-FibonacciNumber.

Codes:

//#define LOCAL

include

int main()
{
#ifdef LOCAL
freopen("E:\Temp\input.txt", "r", stdin);
freopen("E:\Temp\output.txt", "w", stdout);
#endif

int i, n, F[50];
F[0] = 1, F[1] = 1;
scanf("%d", &n);
for(i=2; i<=n; ++i)
F[i] = F[i-1]+F[i-2];
printf("%d\n", F[n]);

return 0;
}

ALDS1_10_C-LongestCommonSubsequence.

Codes: