// Write a Program to take a sorted array arr[] and an integer x as input, find the index (0-based) of the smallest element in arr[] that is greater than or equal to x and print it. This element is called the ceil of x. If such an element does not exist, print -1. Note: In case of multiple occurrences of ceil of x, return the index of the first occurrence.
 
	#include <stdio.h>
 
int main() {
    int n, x;
    scanf("%d", &n);
 
    int arr[n];
    for (int i = 0; i < n; i++) scanf("%d", &arr[i]);
 
    scanf("%d", &x);
 
    int low = 0, high = n - 1, ans = -1;
 
    while (low <= high) {
        int mid = (low + high) / 2;
 
        if (arr[mid] >= x) {
            ans = mid;      // possible ceil
            high = mid - 1; // move left for first occurrence
        } else {
            low = mid + 1;
        }
    }
 
    printf("%d", ans);
    return 0;
}
 
 
 

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