计算数组的前缀最大值

Question

该数组的输入是{4,13,9,10,17,25,35,40,29,48,52,12,15,71,27,32}。我需要比较每个两个元素（如4和13），较大的元素转到临时数组，并与数组中的下一个元素进行比较，以此类推。

我有这个代码，它给我的数组 {13,10,25,40,48,52,71,32,13,40,52,71,40,71} 我需要得到像下面阵列输出 {4,13，13,13，17，25，35，40，40，48，52，52，52，71，71，71}

#include <stdio.h> 
    int main() 
    { 
     int pairmax(int[], int); 
     int premax(int[], int); 
     int i, j, max1, max2, n; 
    n=16; 
    int x[16]={4, 13, 9, 10, 17, 25, 35, 40, 29, 48, 52, 12, 15, 71, 27, 32}; 
     max1 = pairmax(x,n); 
     max2 = premax(x, n); 

     printf("Pairwise max: Largest = %d\n",max1); 
     printf("Prefix max: Largest = %d\n",max2); 
    } 

    int pairmax(int x[], int n) // Implementation of Pairwise Max 
    { 
     int max(int, int); 
     int y[10], i, j; 
     if (n==2) 
      return max(x[0], x[1]); 
     for(i=0, j=0; i<n;i+=2,j++) 
     { 
      if(i < n-1) 
      y[j] = max(x[i], x[i+1]); 
      else 
      y[j] = x[i]; 


    printf("Prefix max: Largest = %d\n",y[j]); 
     } 
     return pairmax(y,j); 
    } 


    int premax(int x[], int n) // Implementation of Prefix Max 
    { 
     int max(int, int); 
     int large, i; 
     large = x[0]; 
     for(i=1; i<n;i++) 
      large = max(large,x[i]); 
     return large; 
    } 

    int max(int a, int b) 
    { 
     if (a > b) 
      return a; 
     else 
      return b; 
    } 

Answer 1

#include <stdio.h> 

int main(void){ 
    int array[] = {4, 13, 9, 10, 17, 25, 35, 40, 29, 48, 52, 12, 15, 71, 27, 32}; 
    int size = sizeof(array)/sizeof(*array); 
    int max = array[0]; 
    int result[size]; 

    for(int i = 0; i < size; ++i){ 
     if(max < array[i]) 
      max = array[i]; 
     result[i] = max; 
    } 
    //print result 
    putchar('{'); 
    for(int i = 0; i < size; ++i){ 
     if(i) 
      putchar(','); 
     printf("%d", result[i]); 
    } 
    putchar('}'); 
    putchar('\n'); 

    return 0; 
}