YoungProgrammer

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Problem 34: Write a program to convert string to integer without library function.

#include<stdio.h>
#include<string.h>

char input[100];

int Convert() {
    int sum = 0, i, p = 1, digit;
    for(i = strlen(input) - 1; i>=0; i--) {
        digit = input[i] - '0';
        sum += digit*p;
        p *= 10;
    }
    return sum;
}
int main() {
    int n;
    scanf("%s",input);
    n = Convert();
    printf("%d\n",n);
    return 0;
}

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