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#include <stdio.h>
int binsearch(int x, int v[], int n);
int binsearch2(int x, int v[], int n);
int
main(void)
{
int v[10]= {1, 2, 3, 4, 5, 6, 7, 8, 9, 11};
printf("%d\n", binsearch(v[5], v, 10));
}
int
binsearch(int x, int v[], int n)
{
int low, high, mid;
low = 0;
high = n-1;
while (low <= high) {
mid = (low+high)/2;
if (x < v[mid])
high = mid - 1;
else if (x > v[mid])
low = mid + 1;
else
return mid;
}
return -1;
}
int
binsearch2(int x, int v[], int n)
{
int low, high, mid;
low = 0;
high = n-1;
while (low < high) {
mid = (low+high)/2;
if (x <= v[mid])
high = mid;
else
low = mid+1;
}
/* here low == high */
return (x == v[low]) ? low : -1;
}
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