# Untitled

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Never
```#include <stdio.h>
#include <string.h>

int main() {
char arr[] = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i',
'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r',
's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I',
'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R',
'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'.', ',', ' ', '?'};

int p, q, n, pn, e, d, k, digits;
char pText[1000];
char cText[1000] = "";

printf("Input the normal text: ");
fgets(pText, sizeof(pText), stdin);
printf("Enter two large prime numbers: ");
scanf("%d %d", &p, &q);

n = p * q;
digits = snprintf(NULL, 0, "%d", n);
pn = (p - 1) * (q - 1);

for (e = 2; e < pn; e++) {
if (pn % e != 0) {
break;
}
}
for(k=1; k<1000; k++){
d = (1 + k*pn) / e;
if(d * e == 1 + k*pn) break;
}

for (int i = 0; pText[i] != '\0'; i++) {
for (int j = 0; j < sizeof(arr); j++) {
if (arr[j] == pText[i]) {
if (j < 10) {
char temp[2];
snprintf(temp, sizeof(temp), "%d", j);
strcat(cText, temp);
} else {
char temp[3];
snprintf(temp, sizeof(temp), "%d", j);
strcat(cText, temp);
}
break;
}
}
}

int x = digits - 1;
int len = strlen(cText);
int numportionss = (len + x - 1) / x;
char portions[1000][10] = {};

int idx = 0;
for (int i = 0; i < numportionss; i++) {
int length = (x < len - idx) ? x : len - idx;
strncpy(portions[i], &cText[idx], length);
idx += length;
}

for (int i = 0; i < numportionss; i++){
int chunkValue = atoi(portions[i]);

int EV = 1;
for (int j = 0; j < e; j++){
EV = (EV * chunkValue) % n;
}

int DV = 1;
for (int j = 0; j < d; j++){
DV = (DV * EV) % n;
}

printf("M%d = %s\t", i + 1, portions[i]);
printf("C%d = %d\t", i + 1, EV);
printf("P%d = %d\n", i + 1, DV);
}
}
```