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// 1416. Restore The Array
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* a progamme was supposed to print an array of integers. the programme forgot
* to print whitespace and the array is printing as a string of digits 's' and
* all we know is that all integers in the array were in the range [1, k] and
* there are no leading zeros in the array. given the string 's' and the integer
* 'k', return the number of possible arrays that can be printed as 's' using
* the mentioned programme. return modulo 10^9+7
*/
int numberOfArrays(char *s, int k) {
const int mod = 1e9 + 7;
int n = strlen(s);
int *dp = calloc(n + 1, sizeof(int));
dp[n] = 1;
for (int i = n - 1; i >= 0; i--) {
if (s[i] == '0')
continue;
long long num = 0;
for (int j = i; j < n; j++) {
num = num * 10 + s[j] - '0';
if (num > k)
break;
dp[i] = (dp[i] + dp[j + 1]) % mod;
}
}
int ans = dp[0];
free(dp);
return ans;
}
int main() {
char s1_2[] = {"1000"}, s3[] = {"1317"};
printf("%d\n", numberOfArrays(s1_2, 10000)); // expect: 1
printf("%d\n", numberOfArrays(s1_2, 10)); // expect: 0
printf("%d\n", numberOfArrays(s3, 2000)); // expect: 8
}
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